---

name: implement-feature description: "Implement an approved feature plan with fresh-context slices, TDD, revision-bound evidence, and PR-ready output." metadata: internal: true triggers: keywords: - implement feature - workflow

Implement Feature Skill

[!IMPORTANT] Implement an approved feature plan with fresh-context slices, TDD, revision-bound evidence, and PR-ready output.

Optional args: slug=, ticket=<id/url>, mode=interactive|autonomous|channel, channel=, auto_continue=true|false, profile=business|hybrid|technical.

Instructions

When the user asks to perform this workflow, execute the following steps:

Implement Feature Workflow

Goal: Build an approved feature through bounded TDD slices and route settled work to verification.

Steps

1. Load plan: Find matching PRD/ticket, SRS/FRS, implementation plan, REQ/AC trace, and skills. Ask if target is ambiguous; route missing trace/test lanes to plan-feature, design-solution, or implementation-readiness. Carry snc_tier/model_tier; high tier adds specialist-architecture-guard and specialist-security-reviewer before verify-work.
2. Prepare workspace: Confirm clean or intentional dirty state; create a branch/worktree only when expected. Provision lockfile dependencies before tests. Report install failures exactly; never claim skipped checks passed.
3. Bound ownership: Assign each slice an owner, exact files, goal/deliverable, in/out scope, authority, REQ/AC IDs, and verification receipt.
4. Implement slices:
   • Record observable contract, distinct fault, smallest honest layer, minimal cases, and exact focused command before testing.
   • Write/update the failing test first; observe expected RED before implementation. Characterize legacy behavior only when needed.
   • Implement the smallest passing change; refactor without scope expansion.
   • Run focused checks foreground, single-run, sequentially, with no peer mutation; classify invalid RED, unexpected GREEN, timeout, or infrastructure failure.
   • Keep concise revision-bound receipts: changed contract, RED/GREEN evidence, behavior smoke, command/result, and limitations.
5. Preserve context: Carry decisions, owner, active slice, and evidence links in the task/plan artifact. Summarize logs; keep source artifacts retrievable.
6. Settle before shared checks: Every owner pauses edits and reports a settled revision. Run one final covering gate, including behavior smoke, foreground/sequentially with no peer mutation. Later edits invalidate affected evidence; rerun those gates and never weaken checks.
7. Handoff: Report final gate/smoke receipts and update REQ/AC trace and walkthrough evidence. Continue only within recorded authority; route to verify-work.

Runtime Contract

• Use for approved plans ready to build; TDD, bounded ownership, revision-bound evidence.
• Required inputs: PRD/ticket with stable REQ/AC trace, owner, and required SRS/test lanes.
• Return BLOCKED only when required trace, owner, or test lanes are missing.

Handoff Payload

• slug, carried operator_profile, snc_tier, model_tier, completed slices, tests run, changed contracts, requirement trace, delegation packets, risks, outcome report, next workflow.
• Carry repository_status and activation_status separately; include authorized next action, settled revision, and evidence links. Publication approval does not grant deployment authority.

Blocking Questions

• Ask max 3 only when an answer changes the result or safety boundary; include a recommended default and 2-3 options.

Output Template

# Implementation Handoff: [Name]
## Completed Slices

## Tests Run

## Changed Contracts

## Requirement Trace Updates
## Evidence

## Known Risks

## Delegation Packets

## Outcome Report

{schema_version: 1, run_id: "[run-id]", slug: "[slug]", workflow: implement-feature, feature_status: implemented, started_at: "[timestamp]", completed_at: "[timestamp]", requirement_trace: {brd_objectives: [], requirements: [], acceptance_criteria: [], srs: []}, completed_evidence: [], missing_evidence: [], decision_needed: [], recommended_next_workflow: verify-work, cost: {source: unavailable}, agent: {identity: "[agent-identity]", model: "[model]"}}
## Next Workflow

verify-work

## Cost Report

Call `get_session_cost(workflow="implement-feature")` before final handoff.