# Execution Transcript

## 1. Task Understanding

The user wants to build an MCP server that wraps an internal issue tracker REST API with approximately 8 endpoints (create issue, update issue, search, add comment, and similar operations). The audience is a small internal engineering team of 5 people. Authentication is simple API key — no OAuth required.

The goal is to expose these issue tracker operations as tools Claude can call through the Model Context Protocol.

## 2. Steps Taken

### Step 1: Read SKILL.md in full

Read `/Users/pedroproenca/Documents/Projects/dot-skills/skills/.experimental/build-mcp-server/SKILL.md`.

The skill defines a 5-phase workflow: Discovery → Deployment model → Tool pattern → Framework → Scaffold. It instructs not to start scaffolding until discovery is complete, but notes that if the user's opening message already answers the questions, acknowledge and skip ahead. The user's message answered all 5 discovery questions, so I ran through Phase 1 mentally rather than asking back.

### Step 2: Run Phase 1 discovery against the user's message

Mapped the user's message to the 5 questions:

| Question | Answer | Source in message |
|---|---|---|
| What does it connect to? | Internal REST API | "internal issue tracker API", "REST API" |
| Who uses it? | Team of 5 engineers | "Just our team uses it (5 engineers)" |
| How many actions? | ~8 | "about 8 endpoints" |
| Mid-call user input? | No | No mention of rich UI or confirmation flows |
| Auth? | API key | "No OAuth, just an API key" |

### Step 3: Apply Phase 2 — determine deployment model

The API is a "cloud API" (internal REST API accessible over the network), not a local process. The skill's decision table puts this squarely in "Remote HTTP server". Even though it's only 5 engineers, remote HTTP is still recommended because:
- One deployment, one config update
- No per-machine runtime dependency
- Can live inside the company network/VPN

The skill identified the relevant reference: `references/remote-http-scaffold.md`.

### Step 4: Apply Phase 3 — pick tool-design pattern

8 endpoints is well under the ~15 threshold for Pattern A (one tool per action). Pattern B (search+execute) is only warranted for dozens to hundreds of endpoints. Chose Pattern A.

The skill identified the relevant reference: `references/tool-design.md`.

### Step 5: Read reference files

Read both references before scaffolding, as the skill directs ("Read these when you reach the relevant phase — not upfront"):

- `references/remote-http-scaffold.md`: Provided the exact TypeScript SDK scaffold pattern — McpServer, StreamableHTTPServerTransport, Express app, stateless transport per request, test commands, connection instructions.
- `references/tool-design.md`: Provided guidance on writing descriptions (say what it does, what it returns, what it doesn't do), tight schemas (enums, min/max, describe every parameter), error returns with next-step hints, read/write annotations, and the tool-count guidance.

### Step 6: Apply Phase 4 — pick framework

Default choice per the skill: Official TypeScript SDK. The skill notes this has best spec coverage and is first to get new features. Python (FastMCP) is equally valid but TypeScript is the recommended default.

### Step 7: Scaffold

Produced three files following the patterns from the reference docs:

1. **`src/server.ts`** — Full MCP server with 8 tools (search_issues, get_issue, list_issues, create_issue, update_issue, add_comment, delete_issue). Each tool has:
   - Tight Zod schemas with `.describe()` on every parameter
   - Descriptions that say what the tool does, what it returns, and when to use another tool instead (sibling disambiguation per tool-design.md)
   - Correct annotations (readOnlyHint for reads, destructiveHint for delete, openWorldHint for mutations, idempotentHint for update)
   - Error returns with recovery hints rather than thrown exceptions
   - Origin validation on `/mcp` (required by MCP spec for DNS rebinding prevention)
   - Health check at `/health` separate from `/mcp`
   - `instructions` field nudging Claude to search before fetching by ID

2. **`src/client.ts`** — IssueTrackerClient wrapping the actual REST API calls. This is the only file that needs to be adapted to the real API's endpoint paths and auth header name. Uses native `fetch` (Node 18+).

3. **`package.json`**, **`tsconfig.json`**, **`.env.example`** — project boilerplate.

4. **`response.md`** — Design recommendation document covering all four decisions and how to connect the team.

## 3. Skill Files Read and Their Influence

### SKILL.md
- Drove the entire workflow structure (5 phases)
- Confirmed this was a "Wrap a small SaaS API → Remote HTTP → One-per-action" scenario (decision matrix at bottom of file)
- Pointed to the two reference files to read
- Specified what the scaffold phase should produce: inline scaffold from remote-http-scaffold.md, no handoff to another skill needed

### references/remote-http-scaffold.md
- Provided the exact SDK import paths (`@modelcontextprotocol/sdk/server/mcp.js`, `@modelcontextprotocol/sdk/server/streamableHttp.js`)
- Showed the stateless transport pattern (fresh transport per request, `sessionIdGenerator: undefined`)
- Provided the Express app pattern (POST /mcp with transport.handleRequest)
- Provided test commands (MCP Inspector CLI flags)
- Provided team connection commands (`claude mcp add --transport http`)
- Included the deployment checklist items used in response.md

### references/tool-design.md
- Drove description style: each description says what it does, what it returns, and explicitly what it does NOT do (e.g. search_issues note about not searching comments)
- Drove sibling disambiguation: get_issue says "use search_issues first if you don't have the ID"; search_issues says "use get_issue to read comments"
- Drove schema tightness: enums for status and priority instead of bare strings, min/max on limit, `.describe()` on every parameter
- Drove error return style: include next-step hints ("Use search_issues to find valid issue IDs") not just error messages
- Drove annotation choices: full annotation table applied to each tool

## 4. Output Produced

| File | Purpose |
|---|---|
| `outputs/response.md` | Full design recommendation + quick start guide |
| `outputs/src/server.ts` | Complete MCP server — 8 tools, Express app, Origin validation |
| `outputs/src/client.ts` | IssueTrackerClient — HTTP wrapper to adapt to real API |
| `outputs/package.json` | npm project config with correct dependencies |
| `outputs/tsconfig.json` | TypeScript config (Node16 modules, strict mode) |
| `outputs/.env.example` | Environment variable template |
| `transcript.md` | This file |
