incorporate openspec

Client now detects whether it was loaded over HTTP or HTTPS and
selects the corresponding API base URL, so both protocols work
without manual config changes.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.claude/commands/opsx/apply.md

@@ -0,0 +1,152 @@
+---
+name: "OPSX: Apply"
+description: Implement tasks from an OpenSpec change (Experimental)
+category: Workflow
+tags: [workflow, artifacts, experimental]
+---
+
+Implement tasks from an OpenSpec change.
+
+**Input**: Optionally specify a change name (e.g., `/opsx:apply add-auth`). If omitted, check if it can be inferred from conversation context. If vague or ambiguous you MUST prompt for available changes.
+
+**Steps**
+
+1. **Select the change**
+
+   If a name is provided, use it. Otherwise:
+   - Infer from conversation context if the user mentioned a change
+   - Auto-select if only one active change exists
+   - If ambiguous, run `openspec list --json` to get available changes and use the **AskUserQuestion tool** to let the user select
+
+   Always announce: "Using change: <name>" and how to override (e.g., `/opsx:apply <other>`).
+
+2. **Check status to understand the schema**
+   ```bash
+   openspec status --change "<name>" --json
+   ```
+   Parse the JSON to understand:
+   - `schemaName`: The workflow being used (e.g., "spec-driven")
+   - Which artifact contains the tasks (typically "tasks" for spec-driven, check status for others)
+
+3. **Get apply instructions**
+
+   ```bash
+   openspec instructions apply --change "<name>" --json
+   ```
+
+   This returns:
+   - Context file paths (varies by schema)
+   - Progress (total, complete, remaining)
+   - Task list with status
+   - Dynamic instruction based on current state
+
+   **Handle states:**
+   - If `state: "blocked"` (missing artifacts): show message, suggest using `/opsx:continue`
+   - If `state: "all_done"`: congratulate, suggest archive
+   - Otherwise: proceed to implementation
+
+4. **Read context files**
+
+   Read the files listed in `contextFiles` from the apply instructions output.
+   The files depend on the schema being used:
+   - **spec-driven**: proposal, specs, design, tasks
+   - Other schemas: follow the contextFiles from CLI output
+
+5. **Show current progress**
+
+   Display:
+   - Schema being used
+   - Progress: "N/M tasks complete"
+   - Remaining tasks overview
+   - Dynamic instruction from CLI
+
+6. **Implement tasks (loop until done or blocked)**
+
+   For each pending task:
+   - Show which task is being worked on
+   - Make the code changes required
+   - Keep changes minimal and focused
+   - Mark task complete in the tasks file: `- [ ]` → `- [x]`
+   - Continue to next task
+
+   **Pause if:**
+   - Task is unclear → ask for clarification
+   - Implementation reveals a design issue → suggest updating artifacts
+   - Error or blocker encountered → report and wait for guidance
+   - User interrupts
+
+7. **On completion or pause, show status**
+
+   Display:
+   - Tasks completed this session
+   - Overall progress: "N/M tasks complete"
+   - If all done: suggest archive
+   - If paused: explain why and wait for guidance
+
+**Output During Implementation**
+
+```
+## Implementing: <change-name> (schema: <schema-name>)
+
+Working on task 3/7: <task description>
+[...implementation happening...]
+✓ Task complete
+
+Working on task 4/7: <task description>
+[...implementation happening...]
+✓ Task complete
+```
+
+**Output On Completion**
+
+```
+## Implementation Complete
+
+**Change:** <change-name>
+**Schema:** <schema-name>
+**Progress:** 7/7 tasks complete ✓
+
+### Completed This Session
+- [x] Task 1
+- [x] Task 2
+...
+
+All tasks complete! You can archive this change with `/opsx:archive`.
+```
+
+**Output On Pause (Issue Encountered)**
+
+```
+## Implementation Paused
+
+**Change:** <change-name>
+**Schema:** <schema-name>
+**Progress:** 4/7 tasks complete
+
+### Issue Encountered
+<description of the issue>
+
+**Options:**
+1. <option 1>
+2. <option 2>
+3. Other approach
+
+What would you like to do?
+```
+
+**Guardrails**
+- Keep going through tasks until done or blocked
+- Always read context files before starting (from the apply instructions output)
+- If task is ambiguous, pause and ask before implementing
+- If implementation reveals issues, pause and suggest artifact updates
+- Keep code changes minimal and scoped to each task
+- Update task checkbox immediately after completing each task
+- Pause on errors, blockers, or unclear requirements - don't guess
+- Use contextFiles from CLI output, don't assume specific file names
+
+**Fluid Workflow Integration**
+
+This skill supports the "actions on a change" model:
+
+- **Can be invoked anytime**: Before all artifacts are done (if tasks exist), after partial implementation, interleaved with other actions
+- **Allows artifact updates**: If implementation reveals design issues, suggest updating artifacts - not phase-locked, work fluidly

.claude/commands/opsx/archive.md

@@ -0,0 +1,157 @@
+---
+name: "OPSX: Archive"
+description: Archive a completed change in the experimental workflow
+category: Workflow
+tags: [workflow, archive, experimental]
+---
+
+Archive a completed change in the experimental workflow.
+
+**Input**: Optionally specify a change name after `/opsx:archive` (e.g., `/opsx:archive add-auth`). If omitted, check if it can be inferred from conversation context. If vague or ambiguous you MUST prompt for available changes.
+
+**Steps**
+
+1. **If no change name provided, prompt for selection**
+
+   Run `openspec list --json` to get available changes. Use the **AskUserQuestion tool** to let the user select.
+
+   Show only active changes (not already archived).
+   Include the schema used for each change if available.
+
+   **IMPORTANT**: Do NOT guess or auto-select a change. Always let the user choose.
+
+2. **Check artifact completion status**
+
+   Run `openspec status --change "<name>" --json` to check artifact completion.
+
+   Parse the JSON to understand:
+   - `schemaName`: The workflow being used
+   - `artifacts`: List of artifacts with their status (`done` or other)
+
+   **If any artifacts are not `done`:**
+   - Display warning listing incomplete artifacts
+   - Prompt user for confirmation to continue
+   - Proceed if user confirms
+
+3. **Check task completion status**
+
+   Read the tasks file (typically `tasks.md`) to check for incomplete tasks.
+
+   Count tasks marked with `- [ ]` (incomplete) vs `- [x]` (complete).
+
+   **If incomplete tasks found:**
+   - Display warning showing count of incomplete tasks
+   - Prompt user for confirmation to continue
+   - Proceed if user confirms
+
+   **If no tasks file exists:** Proceed without task-related warning.
+
+4. **Assess delta spec sync state**
+
+   Check for delta specs at `openspec/changes/<name>/specs/`. If none exist, proceed without sync prompt.
+
+   **If delta specs exist:**
+   - Compare each delta spec with its corresponding main spec at `openspec/specs/<capability>/spec.md`
+   - Determine what changes would be applied (adds, modifications, removals, renames)
+   - Show a combined summary before prompting
+
+   **Prompt options:**
+   - If changes needed: "Sync now (recommended)", "Archive without syncing"
+   - If already synced: "Archive now", "Sync anyway", "Cancel"
+
+   If user chooses sync, use Task tool (subagent_type: "general-purpose", prompt: "Use Skill tool to invoke openspec-sync-specs for change '<name>'. Delta spec analysis: <include the analyzed delta spec summary>"). Proceed to archive regardless of choice.
+
+5. **Perform the archive**
+
+   Create the archive directory if it doesn't exist:
+   ```bash
+   mkdir -p openspec/changes/archive
+   ```
+
+   Generate target name using current date: `YYYY-MM-DD-<change-name>`
+
+   **Check if target already exists:**
+   - If yes: Fail with error, suggest renaming existing archive or using different date
+   - If no: Move the change directory to archive
+
+   ```bash
+   mv openspec/changes/<name> openspec/changes/archive/YYYY-MM-DD-<name>
+   ```
+
+6. **Display summary**
+
+   Show archive completion summary including:
+   - Change name
+   - Schema that was used
+   - Archive location
+   - Spec sync status (synced / sync skipped / no delta specs)
+   - Note about any warnings (incomplete artifacts/tasks)
+
+**Output On Success**
+
+```
+## Archive Complete
+
+**Change:** <change-name>
+**Schema:** <schema-name>
+**Archived to:** openspec/changes/archive/YYYY-MM-DD-<name>/
+**Specs:** ✓ Synced to main specs
+
+All artifacts complete. All tasks complete.
+```
+
+**Output On Success (No Delta Specs)**
+
+```
+## Archive Complete
+
+**Change:** <change-name>
+**Schema:** <schema-name>
+**Archived to:** openspec/changes/archive/YYYY-MM-DD-<name>/
+**Specs:** No delta specs
+
+All artifacts complete. All tasks complete.
+```
+
+**Output On Success With Warnings**
+
+```
+## Archive Complete (with warnings)
+
+**Change:** <change-name>
+**Schema:** <schema-name>
+**Archived to:** openspec/changes/archive/YYYY-MM-DD-<name>/
+**Specs:** Sync skipped (user chose to skip)
+
+**Warnings:**
+- Archived with 2 incomplete artifacts
+- Archived with 3 incomplete tasks
+- Delta spec sync was skipped (user chose to skip)
+
+Review the archive if this was not intentional.
+```
+
+**Output On Error (Archive Exists)**
+
+```
+## Archive Failed
+
+**Change:** <change-name>
+**Target:** openspec/changes/archive/YYYY-MM-DD-<name>/
+
+Target archive directory already exists.
+
+**Options:**
+1. Rename the existing archive
+2. Delete the existing archive if it's a duplicate
+3. Wait until a different date to archive
+```
+
+**Guardrails**
+- Always prompt for change selection if not provided
+- Use artifact graph (openspec status --json) for completion checking
+- Don't block archive on warnings - just inform and confirm
+- Preserve .openspec.yaml when moving to archive (it moves with the directory)
+- Show clear summary of what happened
+- If sync is requested, use the Skill tool to invoke `openspec-sync-specs` (agent-driven)
+- If delta specs exist, always run the sync assessment and show the combined summary before prompting

.claude/commands/opsx/explore.md

@@ -0,0 +1,173 @@
+---
+name: "OPSX: Explore"
+description: "Enter explore mode - think through ideas, investigate problems, clarify requirements"
+category: Workflow
+tags: [workflow, explore, experimental, thinking]
+---
+
+Enter explore mode. Think deeply. Visualize freely. Follow the conversation wherever it goes.
+
+**IMPORTANT: Explore mode is for thinking, not implementing.** You may read files, search code, and investigate the codebase, but you must NEVER write code or implement features. If the user asks you to implement something, remind them to exit explore mode first and create a change proposal. You MAY create OpenSpec artifacts (proposals, designs, specs) if the user asks—that's capturing thinking, not implementing.
+
+**This is a stance, not a workflow.** There are no fixed steps, no required sequence, no mandatory outputs. You're a thinking partner helping the user explore.
+
+**Input**: The argument after `/opsx:explore` is whatever the user wants to think about. Could be:
+- A vague idea: "real-time collaboration"
+- A specific problem: "the auth system is getting unwieldy"
+- A change name: "add-dark-mode" (to explore in context of that change)
+- A comparison: "postgres vs sqlite for this"
+- Nothing (just enter explore mode)
+
+---
+
+## The Stance
+
+- **Curious, not prescriptive** - Ask questions that emerge naturally, don't follow a script
+- **Open threads, not interrogations** - Surface multiple interesting directions and let the user follow what resonates. Don't funnel them through a single path of questions.
+- **Visual** - Use ASCII diagrams liberally when they'd help clarify thinking
+- **Adaptive** - Follow interesting threads, pivot when new information emerges
+- **Patient** - Don't rush to conclusions, let the shape of the problem emerge
+- **Grounded** - Explore the actual codebase when relevant, don't just theorize
+
+---
+
+## What You Might Do
+
+Depending on what the user brings, you might:
+
+**Explore the problem space**
+- Ask clarifying questions that emerge from what they said
+- Challenge assumptions
+- Reframe the problem
+- Find analogies
+
+**Investigate the codebase**
+- Map existing architecture relevant to the discussion
+- Find integration points
+- Identify patterns already in use
+- Surface hidden complexity
+
+**Compare options**
+- Brainstorm multiple approaches
+- Build comparison tables
+- Sketch tradeoffs
+- Recommend a path (if asked)
+
+**Visualize**
+```
+┌─────────────────────────────────────────┐
+│     Use ASCII diagrams liberally        │
+├─────────────────────────────────────────┤
+│                                         │
+│   ┌────────┐         ┌────────┐        │
+│   │ State  │────────▶│ State  │        │
+│   │   A    │         │   B    │        │
+│   └────────┘         └────────┘        │
+│                                         │
+│   System diagrams, state machines,      │
+│   data flows, architecture sketches,    │
+│   dependency graphs, comparison tables  │
+│                                         │
+└─────────────────────────────────────────┘
+```
+
+**Surface risks and unknowns**
+- Identify what could go wrong
+- Find gaps in understanding
+- Suggest spikes or investigations
+
+---
+
+## OpenSpec Awareness
+
+You have full context of the OpenSpec system. Use it naturally, don't force it.
+
+### Check for context
+
+At the start, quickly check what exists:
+```bash
+openspec list --json
+```
+
+This tells you:
+- If there are active changes
+- Their names, schemas, and status
+- What the user might be working on
+
+If the user mentioned a specific change name, read its artifacts for context.
+
+### When no change exists
+
+Think freely. When insights crystallize, you might offer:
+
+- "This feels solid enough to start a change. Want me to create a proposal?"
+- Or keep exploring - no pressure to formalize
+
+### When a change exists
+
+If the user mentions a change or you detect one is relevant:
+
+1. **Read existing artifacts for context**
+   - `openspec/changes/<name>/proposal.md`
+   - `openspec/changes/<name>/design.md`
+   - `openspec/changes/<name>/tasks.md`
+   - etc.
+
+2. **Reference them naturally in conversation**
+   - "Your design mentions using Redis, but we just realized SQLite fits better..."
+   - "The proposal scopes this to premium users, but we're now thinking everyone..."
+
+3. **Offer to capture when decisions are made**
+
+   | Insight Type | Where to Capture |
+   |--------------|------------------|
+   | New requirement discovered | `specs/<capability>/spec.md` |
+   | Requirement changed | `specs/<capability>/spec.md` |
+   | Design decision made | `design.md` |
+   | Scope changed | `proposal.md` |
+   | New work identified | `tasks.md` |
+   | Assumption invalidated | Relevant artifact |
+
+   Example offers:
+   - "That's a design decision. Capture it in design.md?"
+   - "This is a new requirement. Add it to specs?"
+   - "This changes scope. Update the proposal?"
+
+4. **The user decides** - Offer and move on. Don't pressure. Don't auto-capture.
+
+---
+
+## What You Don't Have To Do
+
+- Follow a script
+- Ask the same questions every time
+- Produce a specific artifact
+- Reach a conclusion
+- Stay on topic if a tangent is valuable
+- Be brief (this is thinking time)
+
+---
+
+## Ending Discovery
+
+There's no required ending. Discovery might:
+
+- **Flow into a proposal**: "Ready to start? I can create a change proposal."
+- **Result in artifact updates**: "Updated design.md with these decisions"
+- **Just provide clarity**: User has what they need, moves on
+- **Continue later**: "We can pick this up anytime"
+
+When things crystallize, you might offer a summary - but it's optional. Sometimes the thinking IS the value.
+
+---
+
+## Guardrails
+
+- **Don't implement** - Never write code or implement features. Creating OpenSpec artifacts is fine, writing application code is not.
+- **Don't fake understanding** - If something is unclear, dig deeper
+- **Don't rush** - Discovery is thinking time, not task time
+- **Don't force structure** - Let patterns emerge naturally
+- **Don't auto-capture** - Offer to save insights, don't just do it
+- **Do visualize** - A good diagram is worth many paragraphs
+- **Do explore the codebase** - Ground discussions in reality
+- **Do question assumptions** - Including the user's and your own

.claude/commands/opsx/propose.md

@@ -0,0 +1,106 @@
+---
+name: "OPSX: Propose"
+description: Propose a new change - create it and generate all artifacts in one step
+category: Workflow
+tags: [workflow, artifacts, experimental]
+---
+
+Propose a new change - create the change and generate all artifacts in one step.
+
+I'll create a change with artifacts:
+- proposal.md (what & why)
+- design.md (how)
+- tasks.md (implementation steps)
+
+When ready to implement, run /opsx:apply
+
+---
+
+**Input**: The argument after `/opsx:propose` is the change name (kebab-case), OR a description of what the user wants to build.
+
+**Steps**
+
+1. **If no input provided, ask what they want to build**
+
+   Use the **AskUserQuestion tool** (open-ended, no preset options) to ask:
+   > "What change do you want to work on? Describe what you want to build or fix."
+
+   From their description, derive a kebab-case name (e.g., "add user authentication" → `add-user-auth`).
+
+   **IMPORTANT**: Do NOT proceed without understanding what the user wants to build.
+
+2. **Create the change directory**
+   ```bash
+   openspec new change "<name>"
+   ```
+   This creates a scaffolded change at `openspec/changes/<name>/` with `.openspec.yaml`.
+
+3. **Get the artifact build order**
+   ```bash
+   openspec status --change "<name>" --json
+   ```
+   Parse the JSON to get:
+   - `applyRequires`: array of artifact IDs needed before implementation (e.g., `["tasks"]`)
+   - `artifacts`: list of all artifacts with their status and dependencies
+
+4. **Create artifacts in sequence until apply-ready**
+
+   Use the **TodoWrite tool** to track progress through the artifacts.
+
+   Loop through artifacts in dependency order (artifacts with no pending dependencies first):
+
+   a. **For each artifact that is `ready` (dependencies satisfied)**:
+      - Get instructions:
+        ```bash
+        openspec instructions <artifact-id> --change "<name>" --json
+        ```
+      - The instructions JSON includes:
+        - `context`: Project background (constraints for you - do NOT include in output)
+        - `rules`: Artifact-specific rules (constraints for you - do NOT include in output)
+        - `template`: The structure to use for your output file
+        - `instruction`: Schema-specific guidance for this artifact type
+        - `outputPath`: Where to write the artifact
+        - `dependencies`: Completed artifacts to read for context
+      - Read any completed dependency files for context
+      - Create the artifact file using `template` as the structure
+      - Apply `context` and `rules` as constraints - but do NOT copy them into the file
+      - Show brief progress: "Created <artifact-id>"
+
+   b. **Continue until all `applyRequires` artifacts are complete**
+      - After creating each artifact, re-run `openspec status --change "<name>" --json`
+      - Check if every artifact ID in `applyRequires` has `status: "done"` in the artifacts array
+      - Stop when all `applyRequires` artifacts are done
+
+   c. **If an artifact requires user input** (unclear context):
+      - Use **AskUserQuestion tool** to clarify
+      - Then continue with creation
+
+5. **Show final status**
+   ```bash
+   openspec status --change "<name>"
+   ```
+
+**Output**
+
+After completing all artifacts, summarize:
+- Change name and location
+- List of artifacts created with brief descriptions
+- What's ready: "All artifacts created! Ready for implementation."
+- Prompt: "Run `/opsx:apply` to start implementing."
+
+**Artifact Creation Guidelines**
+
+- Follow the `instruction` field from `openspec instructions` for each artifact type
+- The schema defines what each artifact should contain - follow it
+- Read dependency artifacts for context before creating new ones
+- Use `template` as the structure for your output file - fill in its sections
+- **IMPORTANT**: `context` and `rules` are constraints for YOU, not content for the file
+  - Do NOT copy `<context>`, `<rules>`, `<project_context>` blocks into the artifact
+  - These guide what you write, but should never appear in the output
+
+**Guardrails**
+- Create ALL artifacts needed for implementation (as defined by schema's `apply.requires`)
+- Always read dependency artifacts before creating a new one
+- If context is critically unclear, ask the user - but prefer making reasonable decisions to keep momentum
+- If a change with that name already exists, ask if user wants to continue it or create a new one
+- Verify each artifact file exists after writing before proceeding to next

.claude/skills/openspec-apply-change/SKILL.md

@@ -0,0 +1,156 @@
+---
+name: openspec-apply-change
+description: Implement tasks from an OpenSpec change. Use when the user wants to start implementing, continue implementation, or work through tasks.
+license: MIT
+compatibility: Requires openspec CLI.
+metadata:
+  author: openspec
+  version: "1.0"
+  generatedBy: "1.2.0"
+---
+
+Implement tasks from an OpenSpec change.
+
+**Input**: Optionally specify a change name. If omitted, check if it can be inferred from conversation context. If vague or ambiguous you MUST prompt for available changes.
+
+**Steps**
+
+1. **Select the change**
+
+   If a name is provided, use it. Otherwise:
+   - Infer from conversation context if the user mentioned a change
+   - Auto-select if only one active change exists
+   - If ambiguous, run `openspec list --json` to get available changes and use the **AskUserQuestion tool** to let the user select
+
+   Always announce: "Using change: <name>" and how to override (e.g., `/opsx:apply <other>`).
+
+2. **Check status to understand the schema**
+   ```bash
+   openspec status --change "<name>" --json
+   ```
+   Parse the JSON to understand:
+   - `schemaName`: The workflow being used (e.g., "spec-driven")
+   - Which artifact contains the tasks (typically "tasks" for spec-driven, check status for others)
+
+3. **Get apply instructions**
+
+   ```bash
+   openspec instructions apply --change "<name>" --json
+   ```
+
+   This returns:
+   - Context file paths (varies by schema - could be proposal/specs/design/tasks or spec/tests/implementation/docs)
+   - Progress (total, complete, remaining)
+   - Task list with status
+   - Dynamic instruction based on current state
+
+   **Handle states:**
+   - If `state: "blocked"` (missing artifacts): show message, suggest using openspec-continue-change
+   - If `state: "all_done"`: congratulate, suggest archive
+   - Otherwise: proceed to implementation
+
+4. **Read context files**
+
+   Read the files listed in `contextFiles` from the apply instructions output.
+   The files depend on the schema being used:
+   - **spec-driven**: proposal, specs, design, tasks
+   - Other schemas: follow the contextFiles from CLI output
+
+5. **Show current progress**
+
+   Display:
+   - Schema being used
+   - Progress: "N/M tasks complete"
+   - Remaining tasks overview
+   - Dynamic instruction from CLI
+
+6. **Implement tasks (loop until done or blocked)**
+
+   For each pending task:
+   - Show which task is being worked on
+   - Make the code changes required
+   - Keep changes minimal and focused
+   - Mark task complete in the tasks file: `- [ ]` → `- [x]`
+   - Continue to next task
+
+   **Pause if:**
+   - Task is unclear → ask for clarification
+   - Implementation reveals a design issue → suggest updating artifacts
+   - Error or blocker encountered → report and wait for guidance
+   - User interrupts
+
+7. **On completion or pause, show status**
+
+   Display:
+   - Tasks completed this session
+   - Overall progress: "N/M tasks complete"
+   - If all done: suggest archive
+   - If paused: explain why and wait for guidance
+
+**Output During Implementation**
+
+```
+## Implementing: <change-name> (schema: <schema-name>)
+
+Working on task 3/7: <task description>
+[...implementation happening...]
+✓ Task complete
+
+Working on task 4/7: <task description>
+[...implementation happening...]
+✓ Task complete
+```
+
+**Output On Completion**
+
+```
+## Implementation Complete
+
+**Change:** <change-name>
+**Schema:** <schema-name>
+**Progress:** 7/7 tasks complete ✓
+
+### Completed This Session
+- [x] Task 1
+- [x] Task 2
+...
+
+All tasks complete! Ready to archive this change.
+```
+
+**Output On Pause (Issue Encountered)**
+
+```
+## Implementation Paused
+
+**Change:** <change-name>
+**Schema:** <schema-name>
+**Progress:** 4/7 tasks complete
+
+### Issue Encountered
+<description of the issue>
+
+**Options:**
+1. <option 1>
+2. <option 2>
+3. Other approach
+
+What would you like to do?
+```
+
+**Guardrails**
+- Keep going through tasks until done or blocked
+- Always read context files before starting (from the apply instructions output)
+- If task is ambiguous, pause and ask before implementing
+- If implementation reveals issues, pause and suggest artifact updates
+- Keep code changes minimal and scoped to each task
+- Update task checkbox immediately after completing each task
+- Pause on errors, blockers, or unclear requirements - don't guess
+- Use contextFiles from CLI output, don't assume specific file names
+
+**Fluid Workflow Integration**
+
+This skill supports the "actions on a change" model:
+
+- **Can be invoked anytime**: Before all artifacts are done (if tasks exist), after partial implementation, interleaved with other actions
+- **Allows artifact updates**: If implementation reveals design issues, suggest updating artifacts - not phase-locked, work fluidly

.claude/skills/openspec-archive-change/SKILL.md

@@ -0,0 +1,114 @@
+---
+name: openspec-archive-change
+description: Archive a completed change in the experimental workflow. Use when the user wants to finalize and archive a change after implementation is complete.
+license: MIT
+compatibility: Requires openspec CLI.
+metadata:
+  author: openspec
+  version: "1.0"
+  generatedBy: "1.2.0"
+---
+
+Archive a completed change in the experimental workflow.
+
+**Input**: Optionally specify a change name. If omitted, check if it can be inferred from conversation context. If vague or ambiguous you MUST prompt for available changes.
+
+**Steps**
+
+1. **If no change name provided, prompt for selection**
+
+   Run `openspec list --json` to get available changes. Use the **AskUserQuestion tool** to let the user select.
+
+   Show only active changes (not already archived).
+   Include the schema used for each change if available.
+
+   **IMPORTANT**: Do NOT guess or auto-select a change. Always let the user choose.
+
+2. **Check artifact completion status**
+
+   Run `openspec status --change "<name>" --json` to check artifact completion.
+
+   Parse the JSON to understand:
+   - `schemaName`: The workflow being used
+   - `artifacts`: List of artifacts with their status (`done` or other)
+
+   **If any artifacts are not `done`:**
+   - Display warning listing incomplete artifacts
+   - Use **AskUserQuestion tool** to confirm user wants to proceed
+   - Proceed if user confirms
+
+3. **Check task completion status**
+
+   Read the tasks file (typically `tasks.md`) to check for incomplete tasks.
+
+   Count tasks marked with `- [ ]` (incomplete) vs `- [x]` (complete).
+
+   **If incomplete tasks found:**
+   - Display warning showing count of incomplete tasks
+   - Use **AskUserQuestion tool** to confirm user wants to proceed
+   - Proceed if user confirms
+
+   **If no tasks file exists:** Proceed without task-related warning.
+
+4. **Assess delta spec sync state**
+
+   Check for delta specs at `openspec/changes/<name>/specs/`. If none exist, proceed without sync prompt.
+
+   **If delta specs exist:**
+   - Compare each delta spec with its corresponding main spec at `openspec/specs/<capability>/spec.md`
+   - Determine what changes would be applied (adds, modifications, removals, renames)
+   - Show a combined summary before prompting
+
+   **Prompt options:**
+   - If changes needed: "Sync now (recommended)", "Archive without syncing"
+   - If already synced: "Archive now", "Sync anyway", "Cancel"
+
+   If user chooses sync, use Task tool (subagent_type: "general-purpose", prompt: "Use Skill tool to invoke openspec-sync-specs for change '<name>'. Delta spec analysis: <include the analyzed delta spec summary>"). Proceed to archive regardless of choice.
+
+5. **Perform the archive**
+
+   Create the archive directory if it doesn't exist:
+   ```bash
+   mkdir -p openspec/changes/archive
+   ```
+
+   Generate target name using current date: `YYYY-MM-DD-<change-name>`
+
+   **Check if target already exists:**
+   - If yes: Fail with error, suggest renaming existing archive or using different date
+   - If no: Move the change directory to archive
+
+   ```bash
+   mv openspec/changes/<name> openspec/changes/archive/YYYY-MM-DD-<name>
+   ```
+
+6. **Display summary**
+
+   Show archive completion summary including:
+   - Change name
+   - Schema that was used
+   - Archive location
+   - Whether specs were synced (if applicable)
+   - Note about any warnings (incomplete artifacts/tasks)
+
+**Output On Success**
+
+```
+## Archive Complete
+
+**Change:** <change-name>
+**Schema:** <schema-name>
+**Archived to:** openspec/changes/archive/YYYY-MM-DD-<name>/
+**Specs:** ✓ Synced to main specs (or "No delta specs" or "Sync skipped")
+
+All artifacts complete. All tasks complete.
+```
+
+**Guardrails**
+- Always prompt for change selection if not provided
+- Use artifact graph (openspec status --json) for completion checking
+- Don't block archive on warnings - just inform and confirm
+- Preserve .openspec.yaml when moving to archive (it moves with the directory)
+- Show clear summary of what happened
+- If sync is requested, use openspec-sync-specs approach (agent-driven)
+- If delta specs exist, always run the sync assessment and show the combined summary before prompting

.claude/skills/openspec-explore/SKILL.md

@@ -0,0 +1,288 @@
+---
+name: openspec-explore
+description: Enter explore mode - a thinking partner for exploring ideas, investigating problems, and clarifying requirements. Use when the user wants to think through something before or during a change.
+license: MIT
+compatibility: Requires openspec CLI.
+metadata:
+  author: openspec
+  version: "1.0"
+  generatedBy: "1.2.0"
+---
+
+Enter explore mode. Think deeply. Visualize freely. Follow the conversation wherever it goes.
+
+**IMPORTANT: Explore mode is for thinking, not implementing.** You may read files, search code, and investigate the codebase, but you must NEVER write code or implement features. If the user asks you to implement something, remind them to exit explore mode first and create a change proposal. You MAY create OpenSpec artifacts (proposals, designs, specs) if the user asks—that's capturing thinking, not implementing.
+
+**This is a stance, not a workflow.** There are no fixed steps, no required sequence, no mandatory outputs. You're a thinking partner helping the user explore.
+
+---
+
+## The Stance
+
+- **Curious, not prescriptive** - Ask questions that emerge naturally, don't follow a script
+- **Open threads, not interrogations** - Surface multiple interesting directions and let the user follow what resonates. Don't funnel them through a single path of questions.
+- **Visual** - Use ASCII diagrams liberally when they'd help clarify thinking
+- **Adaptive** - Follow interesting threads, pivot when new information emerges
+- **Patient** - Don't rush to conclusions, let the shape of the problem emerge
+- **Grounded** - Explore the actual codebase when relevant, don't just theorize
+
+---
+
+## What You Might Do
+
+Depending on what the user brings, you might:
+
+**Explore the problem space**
+- Ask clarifying questions that emerge from what they said
+- Challenge assumptions
+- Reframe the problem
+- Find analogies
+
+**Investigate the codebase**
+- Map existing architecture relevant to the discussion
+- Find integration points
+- Identify patterns already in use
+- Surface hidden complexity
+
+**Compare options**
+- Brainstorm multiple approaches
+- Build comparison tables
+- Sketch tradeoffs
+- Recommend a path (if asked)
+
+**Visualize**
+```
+┌─────────────────────────────────────────┐
+│     Use ASCII diagrams liberally        │
+├─────────────────────────────────────────┤
+│                                         │
+│   ┌────────┐         ┌────────┐        │
+│   │ State  │────────▶│ State  │        │
+│   │   A    │         │   B    │        │
+│   └────────┘         └────────┘        │
+│                                         │
+│   System diagrams, state machines,      │
+│   data flows, architecture sketches,    │
+│   dependency graphs, comparison tables  │
+│                                         │
+└─────────────────────────────────────────┘
+```
+
+**Surface risks and unknowns**
+- Identify what could go wrong
+- Find gaps in understanding
+- Suggest spikes or investigations
+
+---
+
+## OpenSpec Awareness
+
+You have full context of the OpenSpec system. Use it naturally, don't force it.
+
+### Check for context
+
+At the start, quickly check what exists:
+```bash
+openspec list --json
+```
+
+This tells you:
+- If there are active changes
+- Their names, schemas, and status
+- What the user might be working on
+
+### When no change exists
+
+Think freely. When insights crystallize, you might offer:
+
+- "This feels solid enough to start a change. Want me to create a proposal?"
+- Or keep exploring - no pressure to formalize
+
+### When a change exists
+
+If the user mentions a change or you detect one is relevant:
+
+1. **Read existing artifacts for context**
+   - `openspec/changes/<name>/proposal.md`
+   - `openspec/changes/<name>/design.md`
+   - `openspec/changes/<name>/tasks.md`
+   - etc.
+
+2. **Reference them naturally in conversation**
+   - "Your design mentions using Redis, but we just realized SQLite fits better..."
+   - "The proposal scopes this to premium users, but we're now thinking everyone..."
+
+3. **Offer to capture when decisions are made**
+
+   | Insight Type | Where to Capture |
+   |--------------|------------------|
+   | New requirement discovered | `specs/<capability>/spec.md` |
+   | Requirement changed | `specs/<capability>/spec.md` |
+   | Design decision made | `design.md` |
+   | Scope changed | `proposal.md` |
+   | New work identified | `tasks.md` |
+   | Assumption invalidated | Relevant artifact |
+
+   Example offers:
+   - "That's a design decision. Capture it in design.md?"
+   - "This is a new requirement. Add it to specs?"
+   - "This changes scope. Update the proposal?"
+
+4. **The user decides** - Offer and move on. Don't pressure. Don't auto-capture.
+
+---
+
+## What You Don't Have To Do
+
+- Follow a script
+- Ask the same questions every time
+- Produce a specific artifact
+- Reach a conclusion
+- Stay on topic if a tangent is valuable
+- Be brief (this is thinking time)
+
+---
+
+## Handling Different Entry Points
+
+**User brings a vague idea:**
+```
+User: I'm thinking about adding real-time collaboration
+
+You: Real-time collab is a big space. Let me think about this...
+
+      COLLABORATION SPECTRUM
+      ════════════════════════════════════════════
+
+      Awareness          Coordination         Sync
+          │                   │                 │
+          ▼                   ▼                 ▼
+      ┌────────┐         ┌────────┐        ┌────────┐
+      │Presence│         │Cursors │        │  CRDT  │
+      │  "3    │         │ Multi  │        │Conflict│
+      │online" │         │ select │        │  free  │
+      └────────┘         └────────┘        └────────┘
+          │                   │                 │
+       trivial            moderate           complex
+
+      Where's your head at?
+```
+
+**User brings a specific problem:**
+```
+User: The auth system is a mess
+
+You: [reads codebase]
+
+     ┌─────────────────────────────────────────────┐
+     │              CURRENT AUTH FLOW              │
+     └─────────────────────────────────────────────┘
+                        │
+          ┌─────────────┼─────────────┐
+          ▼             ▼             ▼
+     ┌─────────┐  ┌─────────┐  ┌─────────┐
+     │ Google  │  │  GitHub │  │  Email  │
+     │  OAuth  │  │  OAuth  │  │  Magic  │
+     └────┬────┘  └────┬────┘  └────┬────┘
+          │             │             │
+          └─────────────┼─────────────┘
+                        ▼
+                  ┌───────────┐
+                  │  Session  │
+                  └─────┬─────┘
+                        │
+                        ▼
+                  ┌───────────┐
+                  │   Perms   │
+                  └───────────┘
+
+     I see three tangles. Which one's burning?
+```
+
+**User is stuck mid-implementation:**
+```
+User: /opsx:explore add-auth-system
+      The OAuth integration is more complex than expected
+
+You: [reads change artifacts]
+
+     You're on task 4: "Implement OAuth flow"
+
+     Let me trace what's involved...
+
+     [draws diagram, explores options, suggests paths]
+
+     Want to update the design to reflect this?
+     Or add a spike task to investigate?
+```
+
+**User wants to compare options:**
+```
+User: Should we use Postgres or SQLite?
+
+You: Generic answer is boring. What's the context?
+
+User: A CLI tool that tracks local dev environments
+
+You: That changes everything.
+
+     ┌─────────────────────────────────────────────────┐
+     │         CLI TOOL DATA STORAGE                  │
+     └─────────────────────────────────────────────────┘
+
+     Key constraints:
+     • No daemon running
+     • Must work offline
+     • Single user
+
+                  SQLite          Postgres
+     Deployment   embedded ✓      needs server ✗
+     Offline      yes ✓           no ✗
+     Single file  yes ✓           no ✗
+
+     SQLite. Not even close.
+
+     Unless... is there a sync component?
+```
+
+---
+
+## Ending Discovery
+
+There's no required ending. Discovery might:
+
+- **Flow into a proposal**: "Ready to start? I can create a change proposal."
+- **Result in artifact updates**: "Updated design.md with these decisions"
+- **Just provide clarity**: User has what they need, moves on
+- **Continue later**: "We can pick this up anytime"
+
+When it feels like things are crystallizing, you might summarize:
+
+```
+## What We Figured Out
+
+**The problem**: [crystallized understanding]
+
+**The approach**: [if one emerged]
+
+**Open questions**: [if any remain]
+
+**Next steps** (if ready):
+- Create a change proposal
+- Keep exploring: just keep talking
+```
+
+But this summary is optional. Sometimes the thinking IS the value.
+
+---
+
+## Guardrails
+
+- **Don't implement** - Never write code or implement features. Creating OpenSpec artifacts is fine, writing application code is not.
+- **Don't fake understanding** - If something is unclear, dig deeper
+- **Don't rush** - Discovery is thinking time, not task time
+- **Don't force structure** - Let patterns emerge naturally
+- **Don't auto-capture** - Offer to save insights, don't just do it
+- **Do visualize** - A good diagram is worth many paragraphs
+- **Do explore the codebase** - Ground discussions in reality
+- **Do question assumptions** - Including the user's and your own

.claude/skills/openspec-propose/SKILL.md

@@ -0,0 +1,110 @@
+---
+name: openspec-propose
+description: Propose a new change with all artifacts generated in one step. Use when the user wants to quickly describe what they want to build and get a complete proposal with design, specs, and tasks ready for implementation.
+license: MIT
+compatibility: Requires openspec CLI.
+metadata:
+  author: openspec
+  version: "1.0"
+  generatedBy: "1.2.0"
+---
+
+Propose a new change - create the change and generate all artifacts in one step.
+
+I'll create a change with artifacts:
+- proposal.md (what & why)
+- design.md (how)
+- tasks.md (implementation steps)
+
+When ready to implement, run /opsx:apply
+
+---
+
+**Input**: The user's request should include a change name (kebab-case) OR a description of what they want to build.
+
+**Steps**
+
+1. **If no clear input provided, ask what they want to build**
+
+   Use the **AskUserQuestion tool** (open-ended, no preset options) to ask:
+   > "What change do you want to work on? Describe what you want to build or fix."
+
+   From their description, derive a kebab-case name (e.g., "add user authentication" → `add-user-auth`).
+
+   **IMPORTANT**: Do NOT proceed without understanding what the user wants to build.
+
+2. **Create the change directory**
+   ```bash
+   openspec new change "<name>"
+   ```
+   This creates a scaffolded change at `openspec/changes/<name>/` with `.openspec.yaml`.
+
+3. **Get the artifact build order**
+   ```bash
+   openspec status --change "<name>" --json
+   ```
+   Parse the JSON to get:
+   - `applyRequires`: array of artifact IDs needed before implementation (e.g., `["tasks"]`)
+   - `artifacts`: list of all artifacts with their status and dependencies
+
+4. **Create artifacts in sequence until apply-ready**
+
+   Use the **TodoWrite tool** to track progress through the artifacts.
+
+   Loop through artifacts in dependency order (artifacts with no pending dependencies first):
+
+   a. **For each artifact that is `ready` (dependencies satisfied)**:
+      - Get instructions:
+        ```bash
+        openspec instructions <artifact-id> --change "<name>" --json
+        ```
+      - The instructions JSON includes:
+        - `context`: Project background (constraints for you - do NOT include in output)
+        - `rules`: Artifact-specific rules (constraints for you - do NOT include in output)
+        - `template`: The structure to use for your output file
+        - `instruction`: Schema-specific guidance for this artifact type
+        - `outputPath`: Where to write the artifact
+        - `dependencies`: Completed artifacts to read for context
+      - Read any completed dependency files for context
+      - Create the artifact file using `template` as the structure
+      - Apply `context` and `rules` as constraints - but do NOT copy them into the file
+      - Show brief progress: "Created <artifact-id>"
+
+   b. **Continue until all `applyRequires` artifacts are complete**
+      - After creating each artifact, re-run `openspec status --change "<name>" --json`
+      - Check if every artifact ID in `applyRequires` has `status: "done"` in the artifacts array
+      - Stop when all `applyRequires` artifacts are done
+
+   c. **If an artifact requires user input** (unclear context):
+      - Use **AskUserQuestion tool** to clarify
+      - Then continue with creation
+
+5. **Show final status**
+   ```bash
+   openspec status --change "<name>"
+   ```
+
+**Output**
+
+After completing all artifacts, summarize:
+- Change name and location
+- List of artifacts created with brief descriptions
+- What's ready: "All artifacts created! Ready for implementation."
+- Prompt: "Run `/opsx:apply` or ask me to implement to start working on the tasks."
+
+**Artifact Creation Guidelines**
+
+- Follow the `instruction` field from `openspec instructions` for each artifact type
+- The schema defines what each artifact should contain - follow it
+- Read dependency artifacts for context before creating new ones
+- Use `template` as the structure for your output file - fill in its sections
+- **IMPORTANT**: `context` and `rules` are constraints for YOU, not content for the file
+  - Do NOT copy `<context>`, `<rules>`, `<project_context>` blocks into the artifact
+  - These guide what you write, but should never appear in the output
+
+**Guardrails**
+- Create ALL artifacts needed for implementation (as defined by schema's `apply.requires`)
+- Always read dependency artifacts before creating a new one
+- If context is critically unclear, ask the user - but prefer making reasonable decisions to keep momentum
+- If a change with that name already exists, ask if user wants to continue it or create a new one
+- Verify each artifact file exists after writing before proceeding to next

.gitignore

@@ -1,218 +1,57 @@
-# ---> Python
-# Byte-compiled / optimized / DLL files
-__pycache__/
-*.py[cod]
-*$py.class
+# ---> .NET / C#
+## Build output
+bin/
+obj/
+publish/
 
-# C extensions
-*.so
+## NuGet
+*.nupkg
+**/packages/
+*.nuget.props
+*.nuget.targets
 
-# Distribution / packaging
-.Python
-build/
-develop-eggs/
-dist/
-downloads/
-eggs/
-.eggs/
-lib/
-lib64/
-parts/
-sdist/
-var/
-wheels/
-share/python-wheels/
-*.egg-info/
-.installed.cfg
-*.egg
-MANIFEST
+## User-specific files
+*.user
+*.suo
+*.userosscache
+*.sln.docstates
 
-# PyInstaller
-#  Usually these files are written by a python script from a template
-#  before PyInstaller builds the exe, so as to inject date/other infos into it.
-*.manifest
-*.spec
-
-# Installer logs
-pip-log.txt
-pip-delete-this-directory.txt
-
-# Unit test / coverage reports
-htmlcov/
-.tox/
-.nox/
-.coverage
-.coverage.*
-.cache
-nosetests.xml
-coverage.xml
-*.cover
-*.py,cover
-.hypothesis/
-.pytest_cache/
-cover/
-
-# Translations
-*.mo
-*.pot
-
-# Django stuff:
-*.log
-local_settings.py
-db.sqlite3
-db.sqlite3-journal
-
-# Flask stuff:
-instance/
-.webassets-cache
-
-# Scrapy stuff:
-.scrapy
-
-# Sphinx documentation
-docs/_build/
-
-# PyBuilder
-.pybuilder/
-target/
-
-# Jupyter Notebook
-.ipynb_checkpoints
-
-# IPython
-profile_default/
-ipython_config.py
-
-# pyenv
-#   For a library or package, you might want to ignore these files since the code is
-#   intended to run in multiple environments; otherwise, check them in:
-# .python-version
-
-# pipenv
-#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
-#   However, in case of collaboration, if having platform-specific dependencies or dependencies
-#   having no cross-platform support, pipenv may install dependencies that don't work, or not
-#   install all needed dependencies.
-#Pipfile.lock
-
-# UV
-#   Similar to Pipfile.lock, it is generally recommended to include uv.lock in version control.
-#   This is especially recommended for binary packages to ensure reproducibility, and is more
-#   commonly ignored for libraries.
-#uv.lock
-
-# poetry
-#   Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control.
-#   This is especially recommended for binary packages to ensure reproducibility, and is more
-#   commonly ignored for libraries.
-#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
-#poetry.lock
-
-# pdm
-#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
-#pdm.lock
-#   pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it
-#   in version control.
-#   https://pdm.fming.dev/latest/usage/project/#working-with-version-control
-.pdm.toml
-.pdm-python
-.pdm-build/
-
-# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
-__pypackages__/
-
-# Celery stuff
-celerybeat-schedule
-celerybeat.pid
-
-# SageMath parsed files
-*.sage.py
-
-# Environments
-.env
-.venv
-env/
-venv/
-ENV/
-env.bak/
-venv.bak/
-
-# Spyder project settings
-.spyderproject
-.spyproject
-
-# Rope project settings
-.ropeproject
-
-# mkdocs documentation
-/site
-
-# mypy
-.mypy_cache/
-.dmypy.json
-dmypy.json
-
-# Pyre type checker
-.pyre/
-
-# pytype static type analyzer
-.pytype/
-
-# Cython debug symbols
-cython_debug/
-
-# PyCharm
-#  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
-#  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
-#  and can be added to the global gitignore or merged into this file.  For a more nuclear
-#  option (not recommended) you can uncomment the following to ignore the entire idea folder.
-#.idea/
-
-# Ruff stuff:
-.ruff_cache/
-
-# PyPI configuration file
-.pypirc
-
-# ---> JupyterNotebooks
-# gitignore template for Jupyter Notebooks
-# website: http://jupyter.org/
-
-.ipynb_checkpoints
-*/.ipynb_checkpoints/*
-
-# IPython
-profile_default/
-ipython_config.py
-
-# Remove previous ipynb_checkpoints
-#   git rm -r .ipynb_checkpoints/
-
-# ---> VisualStudioCode
+## IDE
+.vs/
+.idea/
 .vscode/*
 !.vscode/settings.json
 !.vscode/tasks.json
 !.vscode/launch.json
 !.vscode/extensions.json
-!.vscode/*.code-snippets
 
-# Local History for Visual Studio Code
-.history/
+## Rider
+*.sln.iml
 
-# Built Visual Studio Code Extensions
-*.vsix
+## Blazor WASM publish artifacts
+**/wwwroot/_framework/
 
-# ---> VirtualEnv
-# Virtualenv
-# http://iamzed.com/2009/05/07/a-primer-on-virtualenv/
-.Python
-[Bb]in
-[Ii]nclude
-[Ll]ib
-[Ll]ib64
-[Ll]ocal
-[Ss]cripts
-pyvenv.cfg
-.venv
-pip-selfcheck.json
+## ReSharper / DotSettings
+*.DotSettings.user
+_ReSharper*/
 
+## Test results
+TestResults/
+*.trx
+coverage*.xml
+coverage*.json
+
+## Secrets and environment
+*.env
+appsettings.*.json
+!appsettings.json
+!appsettings.Development.json
+
+## OS files
+.DS_Store
+Thumbs.db
+*.swp
+*~
+
+## Misc
+*.log

CLAUDE.md

@@ -0,0 +1,147 @@
+<!-- GSD:project-start source:PROJECT.md -->
+## Project
+
+**Chat Agent WebApp**
+
+A personal AI chat web application built with Blazor WebAssembly and the OpenAI GPT API. Users send messages, receive streaming AI responses rendered as markdown, and manage multiple persistent conversations. The project doubles as an incremental learning journey — each phase introduces one concept with well-documented, explained code, making it suitable as a Blazor tutorial for a developer experienced in C# but new to the framework.
+
+**Core Value:** A working, well-understood AI chat interface — every line of code is intentional and explained, so the builder learns Blazor patterns while shipping a real product.
+
+### Constraints
+
+- **Tech stack**: .NET / C# / Blazor WebAssembly — non-negotiable
+- **LLM provider**: OpenAI GPT API
+- **Storage**: JSON files on local disk
+- **Architecture**: WASM client + backend API (API key stays server-side)
+- **Code style**: Every Blazor concept introduced must have inline comments explaining what it does and why
+<!-- GSD:project-end -->
+
+<!-- GSD:stack-start source:research/STACK.md -->
+## Technology Stack
+
+## Recommended Stack
+### Core Technologies
+| Technology | Version | Purpose | Why Recommended |
+|------------|---------|---------|-----------------|
+| .NET 9 SDK | 9.x (latest patch) | Runtime, tooling, SDK | LTS-adjacent, stable, .NET 10 is in preview — stay on 9 for a tutorial project targeting a stable foundation |
+| Blazor WebAssembly Standalone | .NET 9 | Client SPA running in-browser | Non-negotiable per project constraints; client-side execution with no server round-trip for UI |
+| ASP.NET Core Web API | .NET 9 | Backend proxy for OpenAI calls | Required to keep the OpenAI API key server-side; WASM cannot access secrets directly |
+| C# 13 | Included with .NET 9 | Application language | Included in .NET 9 SDK; no separate install needed |
+### OpenAI Integration
+| Library | Version | Purpose | Why Recommended |
+|---------|---------|---------|-----------------|
+| `OpenAI` (official) | 2.9.1 | OpenAI API client with streaming | The official OpenAI-published .NET library; supports `CompleteChatStreamingAsync()` returning `AsyncCollectionResult<StreamingChatCompletionUpdate>` via `await foreach`; stable release as of 2026-03-02 |
+### Markdown Rendering
+| Library | Version | Purpose | Why Recommended |
+|---------|---------|---------|-----------------|
+| `Markdig` | 1.1.1 | Parse markdown text to HTML | The de facto standard markdown processor for .NET; CommonMark-compliant, fast, extensible, targets .NET Standard 2.0 so works in WASM; used by Microsoft and Syncfusion as the underlying engine |
+### UI Component Library
+| Library | Version | Purpose | Why Recommended |
+|---------|---------|---------|-----------------|
+| `MudBlazor` | 9.2.0 | Material Design component library | Full .NET 9 support confirmed; pure C# with minimal JavaScript; comprehensive chat-friendly components (MudTextField, MudPaper, MudScrollToBottom, MudList); large community; no per-seat licensing |
+### JSON Storage (Server-side)
+| Technology | Version | Purpose | Why Recommended |
+|------------|---------|---------|-----------------|
+| `System.Text.Json` | Built into .NET 9 | Serialize/deserialize conversation history | Built-in, no extra dependency; `JsonSerializerOptions` with `WriteIndented = true` for human-readable files; async file I/O via `File.ReadAllTextAsync` / `File.WriteAllTextAsync` |
+## Supporting Libraries
+| Library | Version | Purpose | When to Use |
+|---------|---------|---------|-------------|
+| `Microsoft.Extensions.AI` (abstractions) | 9.x preview | Optional AI abstraction layer | Skip for v1 — adds indirection before the core chat pattern is understood. Relevant for v2 when adding multi-provider support |
+| `Blazored.LocalStorage` | latest | Browser local storage | Not needed for this project — persistence is on the server via JSON files, not the browser |
+| `System.Net.ServerSentEvents` | Built into .NET 9 | SSE parser for streaming | Used automatically by the `OpenAI` library on the server; no direct usage needed |
+## Development Tools
+| Tool | Purpose | Notes |
+|------|---------|-------|
+| Visual Studio 2022 (v17.12+) | IDE with Blazor hot reload | Recommended for tutorial builder; full Blazor debugging, component preview, and hot reload support |
+| VS Code + C# Dev Kit | Lighter-weight alternative | Works well; use `dotnet watch` for hot reload |
+| `dotnet watch run` | Hot reload during development | Run in both Client and Server project directories simultaneously |
+| `dotnet-dev-certs` | HTTPS dev certificate | Required for local HTTPS; run `dotnet dev-certs https --trust` once |
+## Installation
+# Create solution
+# Create Blazor WASM client (standalone)
+# Create ASP.NET Core Web API backend
+# Install OpenAI SDK in the API project
+# Install Markdig in the Client project
+## Alternatives Considered
+| Recommended | Alternative | When to Use Alternative |
+|-------------|-------------|-------------------------|
+| `OpenAI` 2.9.1 (official) | `OpenAI-DotNet` 8.8.8 (unofficial) | Never — the official package is now stable and maintained by OpenAI directly |
+| `OpenAI` 2.9.1 (official) | `Azure.AI.OpenAI` 2.1.0 | When targeting Azure OpenAI Service specifically (e.g., enterprise, EU data residency, private endpoints) — overkill for this project |
+| `Markdig` | `CommonMark.NET` | Only if strict CommonMark compliance matters more than extensions; Markdig is a superset and the ecosystem standard |
+| `MudBlazor` | Radzen Blazor | Radzen is fine; choose it if you already know it; MudBlazor has more learning resources |
+| `MudBlazor` | Telerik UI for Blazor | Telerik requires a paid license; not appropriate for a personal tool |
+| Standalone WASM + separate Web API | Blazor Web App template (unified) | Use the unified Blazor Web App template when you want mixed Server+WASM render modes on a single project; overkill for this project and obscures the WASM-specific patterns the tutorial aims to teach |
+| JSON flat files (server-side) | SQLite via EF Core | SQLite is a better choice at scale; JSON is simpler for single-user personal tools and avoids introducing a migration workflow |
+## What NOT to Use
+| Avoid | Why | Use Instead |
+|-------|-----|-------------|
+| `OpenAI-DotNet` (unofficial) | Different API surface, not maintained by OpenAI, version numbers create confusion | Official `OpenAI` NuGet package |
+| `Microsoft.SemanticKernel` | Adds significant abstraction and dependency weight for a tutorial; streaming works but is complex to explain | Direct `OpenAI` SDK calls; add SK in v2 when orchestration is needed |
+| JavaScript `EventSource` API via JSInterop for streaming | Blazor WASM has `SetBrowserResponseStreamingEnabled` which avoids JS interop; adding JSInterop for streaming increases complexity significantly | `HttpCompletionOption.ResponseHeadersRead` + `SetBrowserResponseStreamingEnabled(true)` in the HTTP handler |
+| `Newtonsoft.Json` | Unnecessary dependency; `System.Text.Json` is built into .NET 9 and is faster; Newtonsoft was the pre-.NET Core standard | `System.Text.Json` (built-in) |
+| `Blazored.LocalStorage` for persistence | Browser storage is limited (~5MB), cleared by users, and not suitable for chat history of any meaningful length; also exposes all data client-side | Server-side JSON file storage via the Web API |
+| AOT compilation during learning phase | Dramatically increases build times; not needed until production optimization is a concern; confusing to introduce in a tutorial | Default IL interpretation; add AOT opt-in note in the final phase |
+## Stack Patterns by Variant
+- Backend streams OpenAI tokens as `text/event-stream` (SSE) or `application/x-ndjson`
+- Client uses `SetBrowserResponseStreamingEnabled(true)` on `HttpRequestMessage`
+- Client reads with `HttpCompletionOption.ResponseHeadersRead` and iterates the stream
+- Trigger `StateHasChanged()` in the component after each token to update the UI
+- Define a `ConversationRepository` service on the API that reads/writes from a configurable base path
+- Register as `Singleton` (not `Scoped`) since there is only one user and file access must be serialized
+- Use `SemaphoreSlim(1,1)` to prevent concurrent write conflicts even in single-user mode
+- Use `Markdig.Markdown.ToHtml(text, pipeline)` where `pipeline` is built with `MarkdownPipelineBuilder` enabling extensions (e.g., `UseAutoLinks()`, `UseEmojiAndSmiley()`)
+- Render the HTML string using `@((MarkupString)html)` inside a `<div class="markdown-body">` element
+- Apply CSS (GitHub Markdown CSS or custom) scoped to `.markdown-body` for code blocks and tables
+## Version Compatibility
+| Package | Compatible With | Notes |
+|---------|-----------------|-------|
+| `OpenAI` 2.9.1 | .NET Standard 2.0+ (.NET 9 confirmed) | Published 2026-03-02; requires `System.Net.ServerSentEvents` (built into .NET 9) |
+| `Markdig` 1.1.1 | .NET 8.0, .NET Standard 2.0, .NET Framework 4.6.2 | .NET 9 compatible via .NET 8 TFM; published 2026-03-04 |
+| `MudBlazor` 9.2.0 | .NET 8.0, .NET 9.0, .NET 10.0 | Published 2026-03-18; version 9.x = full support for .NET 9 |
+| .NET 9 SDK | Blazor WASM + Web API in same solution | Both project types target `net9.0`; no cross-framework issues |
+## Sources
+- https://www.nuget.org/packages/OpenAI — Official OpenAI NuGet package; version 2.9.1 confirmed (2026-03-02)
+- https://github.com/openai/openai-dotnet — Official OpenAI .NET SDK; streaming API verified (`CompleteChatStreamingAsync`, `await foreach`)
+- https://www.nuget.org/packages/Markdig — Markdig version 1.1.1 confirmed (2026-03-04)
+- https://www.nuget.org/packages/MudBlazor — MudBlazor 9.2.0 confirmed; .NET 8/9/10 full support (2026-03-18)
+- https://learn.microsoft.com/en-us/aspnet/core/blazor/hosting-models?view=aspnetcore-9.0 — Official Blazor hosting model docs; standalone WASM vs Blazor Web App distinction verified
+- https://learn.microsoft.com/en-us/dotnet/core/compatibility/networking/10.0/default-http-streaming — Breaking change: WASM streaming opt-in (.NET 9) vs default (.NET 10)
+- https://www.strathweb.com/2024/07/built-in-support-for-server-sent-events-in-net-9/ — SSE native support in .NET 9 via `System.Net.ServerSentEvents`; used internally by OpenAI SDK (MEDIUM confidence, single source)
+- https://github.com/openai/openai-dotnet/issues/65 — Confirmed streaming issue in Blazor WASM requires `SetBrowserResponseStreamingEnabled(true)` (MEDIUM confidence, GitHub issue thread)
+- https://devblogs.microsoft.com/dotnet/openai-dotnet-library/ — Official .NET Blog announcement of the OpenAI library
+- https://dev.to/kazinix/blazor-web-app-webassembly-hosted-in-net8-and-net9-1k6g — Hosted template removal in .NET 8+, manual solution structure (MEDIUM confidence)
+<!-- GSD:stack-end -->
+
+<!-- GSD:conventions-start source:CONVENTIONS.md -->
+## Conventions
+
+Conventions not yet established. Will populate as patterns emerge during development.
+<!-- GSD:conventions-end -->
+
+<!-- GSD:architecture-start source:ARCHITECTURE.md -->
+## Architecture
+
+Architecture not yet mapped. Follow existing patterns found in the codebase.
+<!-- GSD:architecture-end -->
+
+<!-- GSD:workflow-start source:GSD defaults -->
+## GSD Workflow Enforcement
+
+Before using Edit, Write, or other file-changing tools, start work through a GSD command so planning artifacts and execution context stay in sync.
+
+Use these entry points:
+- `/gsd:quick` for small fixes, doc updates, and ad-hoc tasks
+- `/gsd:debug` for investigation and bug fixing
+- `/gsd:execute-phase` for planned phase work
+
+Do not make direct repo edits outside a GSD workflow unless the user explicitly asks to bypass it.
+<!-- GSD:workflow-end -->
+
+
+
+<!-- GSD:profile-start -->
+## Developer Profile
+
+> Profile not yet configured. Run `/gsd:profile-user` to generate your developer profile.
+> This section is managed by `generate-claude-profile` -- do not edit manually.
+<!-- GSD:profile-end -->

ChatAgent.sln

@@ -0,0 +1,69 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.0.31903.59
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "src", "src", "{827E0CD3-B72D-47B6-A68D-7590B98EB39B}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ChatAgent.Client", "src\ChatAgent.Client\ChatAgent.Client.csproj", "{600EA0C4-7CDE-4807-BE3C-30A6D2242392}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ChatAgent.Api", "src\ChatAgent.Api\ChatAgent.Api.csproj", "{467D4550-6F9A-456E-B99C-0ABE94070ECF}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ChatAgent.Shared", "src\ChatAgent.Shared\ChatAgent.Shared.csproj", "{06182E3F-BC78-449B-ADF6-D9EE49E48945}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Debug|x64 = Debug|x64
+		Debug|x86 = Debug|x86
+		Release|Any CPU = Release|Any CPU
+		Release|x64 = Release|x64
+		Release|x86 = Release|x86
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{600EA0C4-7CDE-4807-BE3C-30A6D2242392}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{600EA0C4-7CDE-4807-BE3C-30A6D2242392}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{600EA0C4-7CDE-4807-BE3C-30A6D2242392}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{600EA0C4-7CDE-4807-BE3C-30A6D2242392}.Debug|x64.Build.0 = Debug|Any CPU
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+		{467D4550-6F9A-456E-B99C-0ABE94070ECF}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
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+		{467D4550-6F9A-456E-B99C-0ABE94070ECF}.Release|x86.Build.0 = Release|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Debug|x64.Build.0 = Debug|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Debug|x86.Build.0 = Debug|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Release|Any CPU.Build.0 = Release|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Release|x64.ActiveCfg = Release|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Release|x64.Build.0 = Release|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Release|x86.ActiveCfg = Release|Any CPU
+		{06182E3F-BC78-449B-ADF6-D9EE49E48945}.Release|x86.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(NestedProjects) = preSolution
+		{600EA0C4-7CDE-4807-BE3C-30A6D2242392} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
+		{467D4550-6F9A-456E-B99C-0ABE94070ECF} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
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+	EndGlobalSection
+EndGlobal

global.json

@@ -0,0 +1,6 @@
+{
+  "sdk": {
+    "version": "9.0.312",
+    "rollForward": "latestPatch"
+  }
+}

openspec/config.yaml

@@ -0,0 +1,20 @@
+schema: spec-driven
+
+# Project context (optional)
+# This is shown to AI when creating artifacts.
+# Add your tech stack, conventions, style guides, domain knowledge, etc.
+# Example:
+#   context: |
+#     Tech stack: TypeScript, React, Node.js
+#     We use conventional commits
+#     Domain: e-commerce platform
+
+# Per-artifact rules (optional)
+# Add custom rules for specific artifacts.
+# Example:
+#   rules:
+#     proposal:
+#       - Keep proposals under 500 words
+#       - Always include a "Non-goals" section
+#     tasks:
+#       - Break tasks into chunks of max 2 hours

src/ChatAgent.Api/ChatAgent.Api.csproj

@@ -0,0 +1,13 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net9.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\ChatAgent.Shared\ChatAgent.Shared.csproj" />
+  </ItemGroup>
+
+</Project>

src/ChatAgent.Api/Controllers/HealthController.cs

@@ -0,0 +1,47 @@
+// HealthController.cs -- API endpoint that proves the WASM-to-API connection works.
+//
+// This is the first controller in the project. It exists to verify that:
+//   1. The API server starts and responds to HTTP requests
+//   2. CORS allows the Blazor WASM client to call across origins
+//   3. The shared HealthResponse DTO serializes/deserializes correctly
+//
+// In ASP.NET Core, a "controller" is a class that handles HTTP requests.
+// The framework routes requests to controller methods based on attributes.
+
+using ChatAgent.Shared.Models;
+using Microsoft.AspNetCore.Mvc;
+
+namespace ChatAgent.Api.Controllers
+{
+    // [ApiController] enables several conveniences for API development:
+    //   - Automatic HTTP 400 responses for invalid model state
+    //   - Automatic inference of [FromBody] for complex types
+    //   - Problem details responses for error status codes
+    // It signals "this class handles API requests, not HTML pages."
+    [ApiController]
+
+    // [Route("api/[controller]")] maps this class to the URL path /api/health.
+    // The [controller] token is replaced with the class name minus "Controller",
+    // so HealthController becomes "health" -> /api/health.
+    [Route("api/[controller]")]
+    public class HealthController : ControllerBase
+    {
+        // [HttpGet] maps this method to HTTP GET requests at the controller's route.
+        // When a client sends GET /api/health, ASP.NET Core calls this method.
+        // It returns an IActionResult, which gives us control over the HTTP status code.
+        [HttpGet]
+        public IActionResult Get()
+        {
+            // Return HTTP 200 OK with a HealthResponse body.
+            // The framework serializes the object to JSON automatically
+            // because this is an [ApiController].
+            // DateTime.UtcNow provides a live timestamp so the client can verify
+            // the response is fresh (not cached).
+            return Ok(new HealthResponse
+            {
+                Status = "healthy",
+                Timestamp = DateTime.UtcNow
+            });
+        }
+    }
+}

src/ChatAgent.Api/Program.cs

@@ -0,0 +1,59 @@
+// Program.cs -- ASP.NET Core Web API entry point for ChatAgent.
+//
+// This is the backend server. In Phase 1, it only serves a health check endpoint.
+// In later phases, it will proxy OpenAI API calls (keeping the API key server-side)
+// and manage JSON file storage for conversation persistence.
+//
+// ASP.NET Core uses a "builder pattern": first configure services (DI container),
+// then build the app, configure middleware pipeline, and run.
+
+var builder = WebApplication.CreateBuilder(args);
+
+// --- Service Registration (Dependency Injection container) ---
+
+// AddControllers() registers MVC controller services so ASP.NET Core discovers
+// classes decorated with [ApiController]. We use Controllers (not Minimal API)
+// for explicit structure -- each controller is a separate file with clear routing (D-05).
+builder.Services.AddControllers();
+
+// AddCors() registers Cross-Origin Resource Sharing services.
+// CORS is REQUIRED because the Blazor WASM client runs on a different origin
+// (https://localhost:5200) than this API (https://localhost:7100).
+// Browsers block cross-origin HTTP requests by default as a security measure.
+// Without this policy, the client's fetch() calls to the API would be rejected.
+builder.Services.AddCors(options =>
+{
+    options.AddPolicy("AllowBlazorClient", policy =>
+    {
+        policy
+            // Only allow requests from the Blazor WASM client origin
+            .WithOrigins("https://localhost:5200")
+            // Allow any HTTP header (Content-Type, Accept, etc.)
+            .AllowAnyHeader()
+            // Allow any HTTP method (GET, POST, PUT, DELETE, etc.)
+            .AllowAnyMethod();
+    });
+});
+
+var app = builder.Build();
+
+// --- Middleware Pipeline ---
+// Middleware order matters in ASP.NET Core -- each middleware runs in the order
+// it is registered. CORS must be applied before routing and authorization
+// so that preflight (OPTIONS) requests are handled correctly.
+
+// Apply the CORS policy globally -- every response includes the correct
+// Access-Control-Allow-Origin header for the Blazor client's origin.
+app.UseCors("AllowBlazorClient");
+
+// UseAuthorization() enables the authorization middleware. Even though we have
+// no auth in Phase 1, it is included because ASP.NET Core expects it in the
+// pipeline when controllers are used. It is a no-op without [Authorize] attributes.
+app.UseAuthorization();
+
+// MapControllers() scans the assembly for all classes with [ApiController]
+// and maps their routes. This is what connects HealthController's
+// [Route("api/[controller]")] to the URL path /api/health.
+app.MapControllers();
+
+app.Run();

src/ChatAgent.Api/Properties/launchSettings.json

@@ -0,0 +1,23 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": false,
+      "applicationUrl": "http://localhost:7000",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": false,
+      "applicationUrl": "https://localhost:7100;http://localhost:7000",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}

src/ChatAgent.Api/appsettings.Development.json

@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  }
+}

src/ChatAgent.Api/appsettings.json

@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}

src/ChatAgent.Client/App.razor

@@ -0,0 +1,12 @@
+<Router AppAssembly="@typeof(App).Assembly">
+    <Found Context="routeData">
+        <RouteView RouteData="@routeData" DefaultLayout="@typeof(MainLayout)" />
+        <FocusOnNavigate RouteData="@routeData" Selector="h1" />
+    </Found>
+    <NotFound>
+        <PageTitle>Not found</PageTitle>
+        <LayoutView Layout="@typeof(MainLayout)">
+            <p role="alert">Sorry, there's nothing at this address.</p>
+        </LayoutView>
+    </NotFound>
+</Router>

src/ChatAgent.Client/ChatAgent.Client.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk.BlazorWebAssembly">
+
+  <PropertyGroup>
+    <TargetFramework>net9.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly" Version="9.0.14" />
+    <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly.DevServer" Version="9.0.14" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.Extensions.Http" Version="9.0.4" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\ChatAgent.Shared\ChatAgent.Shared.csproj" />
+  </ItemGroup>
+
+</Project>

src/ChatAgent.Client/Layout/MainLayout.razor

@@ -0,0 +1,23 @@
+@* MainLayout.razor -- The root layout component for the application.
+
+   In Blazor, layout components wrap page content. Every routed page (@page)
+   is rendered inside the layout's @Body placeholder. This is similar to
+   _Layout.cshtml in MVC or master pages in Web Forms.
+
+   Phase 1 uses a minimal layout -- just centered content with padding.
+   Later phases will add a sidebar for conversation management.
+*@
+
+@* @inherits LayoutComponentBase makes this a layout component.
+   LayoutComponentBase provides the Body property, which is a RenderFragment
+   containing the routed page's content. Without this base class, @Body
+   would not be available. *@
+@inherits LayoutComponentBase
+
+<main>
+    @* @Body is where the routed page content renders.
+       When the user navigates to "/", the Home.razor component's markup
+       appears here. When they navigate to another @page, that component
+       renders here instead. The layout stays the same -- only @Body changes. *@
+    @Body
+</main>

src/ChatAgent.Client/Layout/MainLayout.razor.css

@@ -0,0 +1,77 @@
+.page {
+    position: relative;
+    display: flex;
+    flex-direction: column;
+}
+
+main {
+    flex: 1;
+}
+
+.sidebar {
+    background-image: linear-gradient(180deg, rgb(5, 39, 103) 0%, #3a0647 70%);
+}
+
+.top-row {
+    background-color: #f7f7f7;
+    border-bottom: 1px solid #d6d5d5;
+    justify-content: flex-end;
+    height: 3.5rem;
+    display: flex;
+    align-items: center;
+}
+
+    .top-row ::deep a, .top-row ::deep .btn-link {
+        white-space: nowrap;
+        margin-left: 1.5rem;
+        text-decoration: none;
+    }
+
+    .top-row ::deep a:hover, .top-row ::deep .btn-link:hover {
+        text-decoration: underline;
+    }
+
+    .top-row ::deep a:first-child {
+        overflow: hidden;
+        text-overflow: ellipsis;
+    }
+
+@media (max-width: 640.98px) {
+    .top-row {
+        justify-content: space-between;
+    }
+
+    .top-row ::deep a, .top-row ::deep .btn-link {
+        margin-left: 0;
+    }
+}
+
+@media (min-width: 641px) {
+    .page {
+        flex-direction: row;
+    }
+
+    .sidebar {
+        width: 250px;
+        height: 100vh;
+        position: sticky;
+        top: 0;
+    }
+
+    .top-row {
+        position: sticky;
+        top: 0;
+        z-index: 1;
+    }
+
+    .top-row.auth ::deep a:first-child {
+        flex: 1;
+        text-align: right;
+        width: 0;
+    }
+
+    .top-row, article {
+        padding-left: 2rem !important;
+        padding-right: 1.5rem !important;
+    }
+}

src/ChatAgent.Client/Layout/NavMenu.razor

@@ -0,0 +1,39 @@
+<div class="top-row ps-3 navbar navbar-dark">
+    <div class="container-fluid">
+        <a class="navbar-brand" href="">ChatAgent.Client</a>
+        <button title="Navigation menu" class="navbar-toggler" @onclick="ToggleNavMenu">
+            <span class="navbar-toggler-icon"></span>
+        </button>
+    </div>
+</div>
+
+<div class="@NavMenuCssClass nav-scrollable" @onclick="ToggleNavMenu">
+    <nav class="nav flex-column">
+        <div class="nav-item px-3">
+            <NavLink class="nav-link" href="" Match="NavLinkMatch.All">
+                <span class="bi bi-house-door-fill-nav-menu" aria-hidden="true"></span> Home
+            </NavLink>
+        </div>
+        <div class="nav-item px-3">
+            <NavLink class="nav-link" href="counter">
+                <span class="bi bi-plus-square-fill-nav-menu" aria-hidden="true"></span> Counter
+            </NavLink>
+        </div>
+        <div class="nav-item px-3">
+            <NavLink class="nav-link" href="weather">
+                <span class="bi bi-list-nested-nav-menu" aria-hidden="true"></span> Weather
+            </NavLink>
+        </div>
+    </nav>
+</div>
+
+@code {
+    private bool collapseNavMenu = true;
+
+    private string? NavMenuCssClass => collapseNavMenu ? "collapse" : null;
+
+    private void ToggleNavMenu()
+    {
+        collapseNavMenu = !collapseNavMenu;
+    }
+}

src/ChatAgent.Client/Layout/NavMenu.razor.css

@@ -0,0 +1,83 @@
+.navbar-toggler {
+    background-color: rgba(255, 255, 255, 0.1);
+}
+
+.top-row {
+    min-height: 3.5rem;
+    background-color: rgba(0,0,0,0.4);
+}
+
+.navbar-brand {
+    font-size: 1.1rem;
+}
+
+.bi {
+    display: inline-block;
+    position: relative;
+    width: 1.25rem;
+    height: 1.25rem;
+    margin-right: 0.75rem;
+    top: -1px;
+    background-size: cover;
+}
+
+.bi-house-door-fill-nav-menu {
+    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='white' class='bi bi-house-door-fill' viewBox='0 0 16 16'%3E%3Cpath d='M6.5 14.5v-3.505c0-.245.25-.495.5-.495h2c.25 0 .5.25.5.5v3.5a.5.5 0 0 0 .5.5h4a.5.5 0 0 0 .5-.5v-7a.5.5 0 0 0-.146-.354L13 5.793V2.5a.5.5 0 0 0-.5-.5h-1a.5.5 0 0 0-.5.5v1.293L8.354 1.146a.5.5 0 0 0-.708 0l-6 6A.5.5 0 0 0 1.5 7.5v7a.5.5 0 0 0 .5.5h4a.5.5 0 0 0 .5-.5Z'/%3E%3C/svg%3E");
+}
+
+.bi-plus-square-fill-nav-menu {
+    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='white' class='bi bi-plus-square-fill' viewBox='0 0 16 16'%3E%3Cpath d='M2 0a2 2 0 0 0-2 2v12a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V2a2 2 0 0 0-2-2H2zm6.5 4.5v3h3a.5.5 0 0 1 0 1h-3v3a.5.5 0 0 1-1 0v-3h-3a.5.5 0 0 1 0-1h3v-3a.5.5 0 0 1 1 0z'/%3E%3C/svg%3E");
+}
+
+.bi-list-nested-nav-menu {
+    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='white' class='bi bi-list-nested' viewBox='0 0 16 16'%3E%3Cpath fill-rule='evenodd' d='M4.5 11.5A.5.5 0 0 1 5 11h10a.5.5 0 0 1 0 1H5a.5.5 0 0 1-.5-.5zm-2-4A.5.5 0 0 1 3 7h10a.5.5 0 0 1 0 1H3a.5.5 0 0 1-.5-.5zm-2-4A.5.5 0 0 1 1 3h10a.5.5 0 0 1 0 1H1a.5.5 0 0 1-.5-.5z'/%3E%3C/svg%3E");
+}
+
+.nav-item {
+    font-size: 0.9rem;
+    padding-bottom: 0.5rem;
+}
+
+    .nav-item:first-of-type {
+        padding-top: 1rem;
+    }
+
+    .nav-item:last-of-type {
+        padding-bottom: 1rem;
+    }
+
+    .nav-item ::deep a {
+        color: #d7d7d7;
+        border-radius: 4px;
+        height: 3rem;
+        display: flex;
+        align-items: center;
+        line-height: 3rem;
+    }
+
+.nav-item ::deep a.active {
+    background-color: rgba(255,255,255,0.37);
+    color: white;
+}
+
+.nav-item ::deep a:hover {
+    background-color: rgba(255,255,255,0.1);
+    color: white;
+}
+
+@media (min-width: 641px) {
+    .navbar-toggler {
+        display: none;
+    }
+
+    .collapse {
+        /* Never collapse the sidebar for wide screens */
+        display: block;
+    }
+
+    .nav-scrollable {
+        /* Allow sidebar to scroll for tall menus */
+        height: calc(100vh - 3.5rem);
+        overflow-y: auto;
+    }
+}

src/ChatAgent.Client/Pages/Counter.razor

@@ -0,0 +1,18 @@
+@page "/counter"
+
+<PageTitle>Counter</PageTitle>
+
+<h1>Counter</h1>
+
+<p role="status">Current count: @currentCount</p>
+
+<button class="btn btn-primary" @onclick="IncrementCount">Click me</button>
+
+@code {
+    private int currentCount = 0;
+
+    private void IncrementCount()
+    {
+        currentCount++;
+    }
+}

src/ChatAgent.Client/Pages/Home.razor

@@ -0,0 +1,86 @@
+@* Home.razor -- The landing page for ChatAgent.
+
+   @page "/" maps this component to the root URL. When a user navigates to "/",
+   the Blazor router renders this component inside MainLayout's @Body placeholder.
+
+   This page demonstrates the health check round-trip:
+   1. On load, it calls the API's /api/health endpoint via ChatApiClient
+   2. Displays the server's health status and timestamp
+   3. Proves CORS is working (WASM on :5200 calling API on :7100)
+*@
+
+@* @page directive maps this component to a URL route.
+   "/" means this is the default/home page. *@
+@page "/"
+
+@* Import the service and model namespaces for this component.
+   These could also be in _Imports.razor for global access. *@
+@using ChatAgent.Client.Services
+@using ChatAgent.Shared.Models
+
+@* @inject requests a service from the Dependency Injection (DI) container.
+   ChatApiClient was registered in Program.cs via AddHttpClient<ChatApiClient>.
+   Blazor creates one instance per component and injects it here. *@
+@inject ChatApiClient ApiClient
+
+<PageTitle>Chat Agent</PageTitle>
+
+<h1>Chat Agent</h1>
+
+@* Conditional rendering: Blazor re-renders the component after OnInitializedAsync completes.
+   We show different content based on the state of our data fields. *@
+
+@if (_healthResponse is null && _error is null)
+{
+    @* Loading state: OnInitializedAsync has not completed yet *@
+    <p class="loading">Checking API connection...</p>
+}
+else if (_healthResponse is not null)
+{
+    @* Success state: API responded with a HealthResponse *@
+    <div class="health-status">
+        <p><strong>API Status:</strong> @_healthResponse.Status</p>
+        <p><strong>Server Time:</strong> @_healthResponse.Timestamp.ToString("yyyy-MM-dd HH:mm:ss UTC")</p>
+    </div>
+}
+else if (_error is not null)
+{
+    @* Error state: the API call failed (network error, CORS blocked, server down, etc.) *@
+    <div class="error-message">
+        <p><strong>Connection Error:</strong> @_error</p>
+    </div>
+}
+
+@code {
+    // Private fields to hold the health check result or error message.
+    // Blazor components use private fields for state that drives the UI.
+    private HealthResponse? _healthResponse;
+    private string? _error;
+
+    /// <summary>
+    /// OnInitializedAsync is a Blazor lifecycle method called once when the component
+    /// is first rendered. It runs after the component receives its initial parameters.
+    ///
+    /// Because it returns Task, Blazor awaits it and automatically calls
+    /// StateHasChanged() when it completes, triggering a re-render.
+    /// This means we do NOT need to call StateHasChanged() manually here.
+    ///
+    /// The component renders twice: once immediately (showing "Checking..."),
+    /// and again after this method completes (showing the result or error).
+    /// </summary>
+    protected override async Task OnInitializedAsync()
+    {
+        try
+        {
+            // Call the API health endpoint via our typed HttpClient wrapper.
+            // This makes an HTTP GET to https://localhost:7100/api/health.
+            _healthResponse = await ApiClient.GetHealthAsync();
+        }
+        catch (Exception ex)
+        {
+            // Catch any exception (network error, CORS block, timeout, etc.)
+            // and store the message for display in the error UI.
+            _error = $"Failed to reach API: {ex.Message}";
+        }
+    }
+}

src/ChatAgent.Client/Pages/Weather.razor

@@ -0,0 +1,57 @@
+@page "/weather"
+@inject HttpClient Http
+
+<PageTitle>Weather</PageTitle>
+
+<h1>Weather</h1>
+
+<p>This component demonstrates fetching data from the server.</p>
+
+@if (forecasts == null)
+{
+    <p><em>Loading...</em></p>
+}
+else
+{
+    <table class="table">
+        <thead>
+            <tr>
+                <th>Date</th>
+                <th aria-label="Temperature in Celsius">Temp. (C)</th>
+                <th aria-label="Temperature in Farenheit">Temp. (F)</th>
+                <th>Summary</th>
+            </tr>
+        </thead>
+        <tbody>
+            @foreach (var forecast in forecasts)
+            {
+                <tr>
+                    <td>@forecast.Date.ToShortDateString()</td>
+                    <td>@forecast.TemperatureC</td>
+                    <td>@forecast.TemperatureF</td>
+                    <td>@forecast.Summary</td>
+                </tr>
+            }
+        </tbody>
+    </table>
+}
+
+@code {
+    private WeatherForecast[]? forecasts;
+
+    protected override async Task OnInitializedAsync()
+    {
+        forecasts = await Http.GetFromJsonAsync<WeatherForecast[]>("sample-data/weather.json");
+    }
+
+    public class WeatherForecast
+    {
+        public DateOnly Date { get; set; }
+
+        public int TemperatureC { get; set; }
+
+        public string? Summary { get; set; }
+
+        public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
+    }
+}

src/ChatAgent.Client/Program.cs

@@ -0,0 +1,52 @@
+// Program.cs -- Blazor WebAssembly application entry point for ChatAgent.
+//
+// This is where the WASM client is configured and launched. Unlike a server-side
+// ASP.NET Core app, a Blazor WASM app runs entirely in the browser. The
+// WebAssemblyHostBuilder configures:
+//   - Root components (what gets rendered into the HTML page)
+//   - Services (dependency injection container, similar to server-side DI)
+//   - Configuration (reads from wwwroot/appsettings.json)
+//
+// This file will grow as we add more services in later phases (e.g., chat state management).
+
+using Microsoft.AspNetCore.Components.Web;
+using Microsoft.AspNetCore.Components.WebAssembly.Hosting;
+using ChatAgent.Client;
+using ChatAgent.Client.Services;
+
+var builder = WebAssemblyHostBuilder.CreateDefault(args);
+
+// Add<App>("#app") tells Blazor to render the App component inside the
+// <div id="app"> element in wwwroot/index.html. This is the "mount point"
+// for the entire Blazor component tree.
+builder.RootComponents.Add<App>("#app");
+
+// HeadOutlet allows Razor components to modify <head> elements (e.g., <title>)
+// using the <PageTitle> and <HeadContent> components. "head::after" means
+// content is appended after existing head elements.
+builder.RootComponents.Add<HeadOutlet>("head::after");
+
+// Determine the API base URL by matching the protocol the app was loaded with.
+// In Blazor WASM, builder.HostEnvironment.BaseAddress is the URL the browser
+// used to load the app (e.g., "http://localhost:5100/" or "https://localhost:5200/").
+// We check if the app was loaded over HTTPS and pick the corresponding API URL.
+// IMPORTANT: wwwroot/ files are PUBLIC -- they are downloaded to the browser.
+// Never put secrets (API keys, passwords) in appsettings.json for a WASM app.
+// The API key lives server-side in the ChatAgent.Api project.
+var isHttps = builder.HostEnvironment.BaseAddress.StartsWith("https://", StringComparison.OrdinalIgnoreCase);
+var apiBaseUrl = isHttps
+    ? builder.Configuration["ApiBaseUrl_Https"] ?? "https://localhost:7100"
+    : builder.Configuration["ApiBaseUrl_Http"] ?? "http://localhost:7000";
+
+// AddHttpClient<ChatApiClient> registers a typed HttpClient using IHttpClientFactory.
+// IHttpClientFactory manages the underlying HttpMessageHandler lifetime to prevent
+// socket exhaustion (a common problem with raw HttpClient in long-running apps).
+// The lambda configures the client with the API base URL so ChatApiClient
+// does not need to know the URL -- it is injected with a pre-configured HttpClient.
+// In Blazor WASM, HttpClient uses the browser's Fetch API under the hood.
+builder.Services.AddHttpClient<ChatApiClient>(client =>
+{
+    client.BaseAddress = new Uri(apiBaseUrl);
+});
+
+await builder.Build().RunAsync();

src/ChatAgent.Client/Properties/launchSettings.json

@@ -0,0 +1,25 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "inspectUri": "{wsProtocol}://{url.hostname}:{url.port}/_framework/debug/ws-proxy?browser={browserInspectUri}",
+      "applicationUrl": "http://localhost:5100",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "inspectUri": "{wsProtocol}://{url.hostname}:{url.port}/_framework/debug/ws-proxy?browser={browserInspectUri}",
+      "applicationUrl": "https://localhost:5200;http://localhost:5100",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}

src/ChatAgent.Client/Services/ChatApiClient.cs

@@ -0,0 +1,53 @@
+// ChatApiClient.cs -- Typed HttpClient wrapper for communicating with the ChatAgent API.
+//
+// WHY A TYPED CLIENT? Instead of injecting HttpClient directly into components,
+// we wrap it in a dedicated service class. This follows the "typed client" pattern (D-04):
+//   - Components depend on ChatApiClient, not HttpClient (loose coupling)
+//   - API URL paths are centralized here, not scattered across components
+//   - Easy to mock for testing -- swap ChatApiClient, not HttpClient
+//   - IHttpClientFactory manages the underlying HttpClient lifetime
+//
+// In Blazor WASM, HttpClient is backed by the browser's Fetch API.
+// The base URL is configured in Program.cs via AddHttpClient<ChatApiClient>.
+
+using System.Net.Http.Json;
+using ChatAgent.Shared.Models;
+
+namespace ChatAgent.Client.Services
+{
+    /// <summary>
+    /// Typed HttpClient for the ChatAgent API. Each public method maps to one API endpoint.
+    /// Constructor injection of HttpClient is provided by IHttpClientFactory,
+    /// which was configured in Program.cs with the API base URL.
+    /// </summary>
+    public class ChatApiClient
+    {
+        // The HttpClient instance is injected by the DI container (IHttpClientFactory).
+        // It is pre-configured with BaseAddress pointing to the API server.
+        private readonly HttpClient _httpClient;
+
+        /// <summary>
+        /// Constructor receives an HttpClient from IHttpClientFactory DI registration.
+        /// The client is already configured with the API base URL.
+        /// </summary>
+        public ChatApiClient(HttpClient httpClient)
+        {
+            _httpClient = httpClient;
+        }
+
+        /// <summary>
+        /// Calls GET /api/health on the API server and deserializes the JSON response
+        /// into a HealthResponse object. Returns null if deserialization fails.
+        ///
+        /// GetFromJsonAsync is an extension method from System.Net.Http.Json that
+        /// combines the HTTP GET call and JSON deserialization into a single step.
+        /// It uses System.Text.Json internally (the built-in .NET JSON serializer).
+        /// </summary>
+        public async Task<HealthResponse?> GetHealthAsync()
+        {
+            // "api/health" is a relative URL -- it is appended to the BaseAddress
+            // configured in Program.cs (e.g., https://localhost:7100/api/health).
+            return await _httpClient.GetFromJsonAsync<HealthResponse>("api/health");
+        }
+    }
+}

src/ChatAgent.Client/_Imports.razor

@@ -0,0 +1,19 @@
+@* _Imports.razor -- Global using directives for all .razor files in this project.
+
+   Any @using directive placed here is automatically available in every .razor file
+   in the ChatAgent.Client project. This avoids repeating common imports in each component.
+   It works like a "global usings" file but specifically for Razor components.
+*@
+
+@using System.Net.Http
+@using System.Net.Http.Json
+@using Microsoft.AspNetCore.Components.Forms
+@using Microsoft.AspNetCore.Components.Routing
+@using Microsoft.AspNetCore.Components.Web
+@using Microsoft.AspNetCore.Components.Web.Virtualization
+@using Microsoft.AspNetCore.Components.WebAssembly.Http
+@using Microsoft.JSInterop
+@using ChatAgent.Client
+@using ChatAgent.Client.Layout
+@using ChatAgent.Client.Services
+@using ChatAgent.Shared.Models

src/ChatAgent.Client/wwwroot/appsettings.json

@@ -0,0 +1,4 @@
+{
+  "ApiBaseUrl_Http": "http://localhost:7000",
+  "ApiBaseUrl_Https": "https://localhost:7100"
+}

src/ChatAgent.Client/wwwroot/css/app.css

@@ -0,0 +1,117 @@
+/* app.css -- Application styles for ChatAgent (Phase 1).
+ *
+ * Phase 1 uses plain HTML/CSS (D-10) with a light theme (D-11).
+ * MudBlazor will be introduced in Phase 5 for UI polish.
+ * These styles provide a clean, minimal appearance for the health check page.
+ */
+
+html, body {
+    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+    margin: 0;
+    padding: 0;
+    background-color: #ffffff;
+    color: #333333;
+}
+
+main {
+    max-width: 800px;
+    margin: 0 auto;
+    padding: 2rem;
+}
+
+h1 {
+    color: #1a1a1a;
+    margin-bottom: 1.5rem;
+}
+
+.health-status {
+    padding: 1rem;
+    border: 1px solid #e0e0e0;
+    border-radius: 8px;
+    background-color: #f9f9f9;
+}
+
+.health-status p {
+    margin: 0.5rem 0;
+}
+
+.error-message {
+    color: #d32f2f;
+    padding: 1rem;
+    border: 1px solid #d32f2f;
+    border-radius: 8px;
+    background-color: #fce4ec;
+}
+
+.loading {
+    color: #666666;
+    font-style: italic;
+}
+
+/* Blazor error UI -- shown when an unhandled exception occurs.
+ * This is built into the Blazor template's index.html and should be kept. */
+#blazor-error-ui {
+    color-scheme: light only;
+    background: lightyellow;
+    bottom: 0;
+    box-shadow: 0 -1px 2px rgba(0, 0, 0, 0.2);
+    box-sizing: border-box;
+    display: none;
+    left: 0;
+    padding: 0.6rem 1.25rem 0.7rem 1.25rem;
+    position: fixed;
+    width: 100%;
+    z-index: 1000;
+}
+
+#blazor-error-ui .dismiss {
+    cursor: pointer;
+    position: absolute;
+    right: 0.75rem;
+    top: 0.5rem;
+}
+
+.blazor-error-boundary {
+    background: url(data:image/svg+xml;base64,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) no-repeat 1rem/1.8rem, #b32121;
+    padding: 1rem 1rem 1rem 3.7rem;
+    color: white;
+}
+
+.blazor-error-boundary::after {
+    content: "An error has occurred."
+}
+
+/* Loading progress indicator -- shown while the WASM runtime downloads.
+ * This SVG-based progress circle is defined in index.html. */
+.loading-progress {
+    position: relative;
+    display: block;
+    width: 8rem;
+    height: 8rem;
+    margin: 20vh auto 1rem auto;
+}
+
+.loading-progress circle {
+    fill: none;
+    stroke: #e0e0e0;
+    stroke-width: 0.6rem;
+    transform-origin: 50% 50%;
+    transform: rotate(-90deg);
+}
+
+.loading-progress circle:last-child {
+    stroke: #1b6ec2;
+    stroke-dasharray: calc(3.141 * var(--blazor-load-percentage, 0%) * 0.8), 500%;
+    transition: stroke-dasharray 0.05s ease-in-out;
+}
+
+.loading-progress-text {
+    position: absolute;
+    text-align: center;
+    font-weight: bold;
+    inset: calc(20vh + 3.25rem) 0 auto 0.2rem;
+}
+
+.loading-progress-text:after {
+    content: var(--blazor-load-percentage-text, "Loading");
+}

src/ChatAgent.Client/wwwroot/index.html

@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>ChatAgent.Client</title>
+    <base href="/" />
+    <link rel="stylesheet" href="lib/bootstrap/dist/css/bootstrap.min.css" />
+    <link rel="stylesheet" href="css/app.css" />
+    <link rel="icon" type="image/png" href="favicon.png" />
+    <link href="ChatAgent.Client.styles.css" rel="stylesheet" />
+</head>
+
+<body>
+    <div id="app">
+        <svg class="loading-progress">
+            <circle r="40%" cx="50%" cy="50%" />
+            <circle r="40%" cx="50%" cy="50%" />
+        </svg>
+        <div class="loading-progress-text"></div>
+    </div>
+
+    <div id="blazor-error-ui">
+        An unhandled error has occurred.
+        <a href="." class="reload">Reload</a>
+        <span class="dismiss">🗙</span>
+    </div>
+    <script src="_framework/blazor.webassembly.js"></script>
+</body>
+
+</html>

src/ChatAgent.Client/wwwroot/sample-data/weather.json

@@ -0,0 +1,27 @@
+[
+  {
+    "date": "2022-01-06",
+    "temperatureC": 1,
+    "summary": "Freezing"
+  },
+  {
+    "date": "2022-01-07",
+    "temperatureC": 14,
+    "summary": "Bracing"
+  },
+  {
+    "date": "2022-01-08",
+    "temperatureC": -13,
+    "summary": "Freezing"
+  },
+  {
+    "date": "2022-01-09",
+    "temperatureC": -16,
+    "summary": "Balmy"
+  },
+  {
+    "date": "2022-01-10",
+    "temperatureC": -2,
+    "summary": "Chilly"
+  }
+]

src/ChatAgent.Shared/ChatAgent.Shared.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net9.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

src/ChatAgent.Shared/Models/HealthResponse.cs

@@ -0,0 +1,32 @@
+// HealthResponse.cs -- Shared Data Transfer Object (DTO) for the health check endpoint.
+//
+// WHY SHARED? This class lives in the ChatAgent.Shared project, which is referenced by
+// both the API (ChatAgent.Api) and the client (ChatAgent.Client). By sharing the type:
+//   - The API serializes a HealthResponse to JSON when responding to GET /api/health
+//   - The Client deserializes that same JSON back into a HealthResponse object
+//   - Both sides agree on the shape of the data -- no mismatched property names or types
+//
+// This is the "shared contract" pattern: one type definition, two consumers.
+
+namespace ChatAgent.Shared.Models
+{
+    /// <summary>
+    /// Data Transfer Object (DTO) returned by the API health check endpoint.
+    /// Contains the server's health status and current timestamp to prove
+    /// the response is live (not cached or stale).
+    /// </summary>
+    public class HealthResponse
+    {
+        /// <summary>
+        /// Server health status string (e.g., "healthy").
+        /// Initialized to empty string to avoid null warnings with nullable enabled.
+        /// </summary>
+        public string Status { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Server-side UTC timestamp at the moment the health check ran.
+        /// The client displays this to confirm the response is fresh.
+        /// </summary>
+        public DateTime Timestamp { get; set; }
+    }
+}