implement

name	implement
description	Implement a spec generated by /spec. Reads .claude/specs/{slug}/design.md, executes each task in Section 8 in order, marks tasks complete as it goes, verifies acceptance after each task, and stops on failure. Invoke when the user says "implement issue
disable-model-invocation	true
allowed-tools	Read Edit Write Bash(git *) Bash(nx *) Bash(dotnet *) Bash(mkdir *) Bash(find *) Bash(ls *) mcp__github__add_issue_comment mcp__github__get_issue
arguments	["issue"]

git branch --show-current

ls "${CLAUDE_PROJECT_DIR}/.claude/specs/"

Inputs

• Issue number: $issue
• Project root: use ${CLAUDE_PROJECT_DIR}, already available in session context
• Today's date: use the current date already available in session context
• Current branch: taken from the git branch --show-current output above
• Available specs: taken from the ls output above (if empty or the directory doesn't exist, treat as no specs yet — run /spec first)

---

Step 1 — Locate the spec

Find the spec directory by scanning AVAILABLE_SPECS for an entry that starts with $issue-.

• Exactly one match: use it. Full spec path: {PROJECT_DIR}/.claude/specs/{slug}/design.md
• Zero matches: stop. Print: No spec found for issue #$issue. Run /spec $issue first.
• Multiple matches: stop. Print all matches and ask the user to re-run with the full slug.

---

Step 2 — Read the spec

Read the full design.md. Extract and hold in memory:

• Title and issue number from the H1 heading: # Spec: {title} (#{N})
• Bounded Context and Layers from the metadata blockquote at the top
• All tasks from Section 8 "Implementation Tasks":
  • Lines matching - [ ] **TASK-NN** → pending (will execute)
  • Lines matching - [x] **TASK-NN** → already done (skip)
  • For each pending task: task ID, title, full **What:** block, full **Acceptance:** block
• Sections 5–7 (API Design, Data Model Changes, Frontend Changes) as implementation reference

---

Step 3 — Ensure correct git branch

Check CURRENT_BRANCH:

• If master or main: run git checkout -b feature/{slug}, then print Created branch feature/{slug}.
• If already a branch matching the spec slug: proceed silently.
• If a different unrelated branch: print Warning: working on branch {branch}, not feature/{slug}. Continuing. Do not abort.

---

Step 4 — Execute tasks in order

Work through pending tasks in TASK-NN ascending order. For each:

Print before starting:

▶ TASK-NN — {title}

Execute — read the "What" field and implement it. Follow these rules without exception:

• .Api.Rest projects contain only controllers, DTO mapping, and routing. No business logic.
• Commands and command handlers go in {Ctx}.Application.Write.
• Queries and query handlers go in {Ctx}.Application.Read.
• Domain logic (entities, value objects, domain events, invariants) goes in {Ctx}.Domain.
• EF Core configuration and migrations go in {Ctx}.Persistence.Context.
• New Angular components are standalone. SCSS is co-located. Use path aliases (@stories/*, @shared/*, @media/*, @users/*, @user-to-story/*, @admin/*) for all cross-folder imports — never use relative paths that cross domain boundaries.
• EF Core migrations: run dotnet ef migrations add {Name} --project server/src/Hiscary.{Ctx}.Persistence.Context. Never hand-edit the generated file.
• Write no comments that explain what the code does. Only comment on non-obvious constraints or workarounds.

Verify — read the "Acceptance" field and execute it exactly:

• Command to run (e.g. dotnet build, nx test hiscaries-client): run it and check exit code.
• HTTP response check: describe the exact curl or request to make and pause for the user to confirm.
• If the acceptance check fails:

  ✗ TASK-NN failed: {specific error or output that caused failure}
  Stopping. Fix the issue above and re-run /implement $issue to resume.
  

  Stop immediately. Do not proceed to the next task.

Mark complete — only if acceptance passed:

Edit design.md: change - [ ] **TASK-NN** to - [x] **TASK-NN** (match the first occurrence of that exact task ID).

Print:

✓ TASK-NN — {title}

---

Step 5 — Final acceptance check

After all tasks are marked [x], print:

All tasks complete. Running final acceptance check...

Run the appropriate checks based on the Layers extracted in Step 2:

• Angular frontend or NgRx state in layers:

  cd {PROJECT_DIR}/client && nx build hiscaries-client && nx test hiscaries-client
  

• Any backend layer (.NET API controller, Application layer, Domain model, EF Core/Postgres, etc.):

  dotnet build {PROJECT_DIR}/server/src/Hiscary.AppHost
  

• If {Ctx}.IntegrationTests project exists for the bounded context:

  dotnet test {PROJECT_DIR}/server/src/Hiscary.{Ctx}.IntegrationTests
  

If all pass: proceed to Step 6.

If any fail: print the failure output and stop. Do not post a GitHub comment.

---

Step 6 — Post GitHub comment and report

Parse owner and repo from:

git remote get-url origin

Strip the github.com: or github.com/ prefix and the .git suffix.

Call mcp__github__add_issue_comment:

• owner: parsed above
• repo: parsed above
• issue_number: $issue
• body:

## Implementation complete 🎉

All tasks from the spec have been implemented and verified.

**Branch:** `feature/{slug}`
**Tasks completed:** {N}
**Layers touched:** {layers from spec metadata}

**Completed tasks:**
{TASK-01 — title}
{TASK-02 — title}
...

Next step: run `/ship` to commit, push, and open a PR.

Then print locally:

Done. {N} tasks implemented on branch feature/{slug}.
Run /ship to create the PR.