| name | feature-dev |
| description | Feature development workflow. Use when: implementing features, writing code, running dev loop. Not for: understanding code (use code-explore), reviewing code (use codex-code-review). Output: implemented feature + tests + review gate. |
| allowed-tools | Read, Grep, Glob, Edit, Write, Bash, Skill, AskUserQuestion, mcp__codex__codex, mcp__codex__codex-reply |
Feature Development Skill
Trigger
- Keywords: develop feature, implement, write code, verify, precommit, refactor, simplify
When NOT to Use
- Just want to understand code (use Explore)
- Review code only (use codex-code-review)
- Review documents only (use doc-review)
- Pure test-only tasks without feature changes (use
/codex-test-review directly)
Prohibited Actions
❌ git add | git commit | git push — per @rules/git-workflow.md
This skill implements features but does not commit. /precommit is a quality gate only. To commit, the user must invoke /smart-commit --execute separately.
budget:token_budget200000</budget:token_budget>
Workflow
Requirements → Design → Implement → Test + Review → Precommit Gate → Doc Sync
│ │ │ │ │
▼ ▼ ▼ ▼ ▼
/codex- /codex- /verify /precommit /update-docs
architect implement /codex-test-review (or /precommit) /create-request --update
/codex-review-fast
Design before code: for a non-trivial change, briefly consider who owns each responsibility,
the simplest shape that fits the existing code, and why — and say what you chose when the choice
is non-obvious. Principles (clear names, small cohesive functions, dependency direction,
composition where it reduces coupling) are questions, not quotas: never add an abstraction to
demonstrate design. /codex-architect is for genuinely hard trade-offs (cross-module boundaries,
new public APIs, durable abstractions), not every feature.
Commands
| Phase | Command | Description |
|---|
| Design | /codex-architect | Get architecture advice |
| Implement | /codex-implement | Codex writes code |
| Test: Run | /verify | Run tests (lint → typecheck → unit → integration) |
| Test: Review | /codex-test-review | Mandatory — review test sufficiency (5 dimensions) |
| Test: Generate | /codex-test-gen | Generate unit tests for gaps |
| Test: Integration | /post-dev-test | Write missing integration/e2e tests |
| Review | /codex-review-fast | Code review (auto-loop) |
| Precommit | /precommit | lint + build + test (auto-loop canonical path) |
| Doc Sync | /update-docs | Sync docs with code |
| Doc Sync | /create-request --update | Update request progress |
| Refactor | /simplify | Final refactoring |
Test + Review Phase (Detail)
This is the core of feature-dev — ensuring sufficient test coverage before code review.
Step 1: Run existing tests
/verify → all tests pass?
Yes → Step 2
No → fix failures → re-run /verify
Step 2: Test adequacy review (mandatory for code changes)
/codex-test-review → ✅ Tests sufficient?
Yes → Step 3
No → close gaps (Step 2a) → /codex-test-review --continue
Step 2a: Gap closure
| Gap Type | Remediation Command |
|---|
| Unit test missing/insufficient | /codex-test-gen → write tests → /verify |
| Integration/E2E missing | /post-dev-test → write tests → /verify |
Step 3: Code review (auto-loop)
/codex-review-fast → ✅ Ready?
Yes → Precommit Gate
No → fix issues → re-run /codex-review-fast (auto-loop)
Freshness rule
If code changes after the latest ✅ Tests sufficient gate (e.g., fixes from code review), rerun /verify then /codex-test-review --continue before proceeding to precommit gate.
Testing Requirements
Follow @rules/testing.md for conventions (AAA, naming, evidence model).
Follow @rules/testing-project.md for project-specific overrides (directories, runner, adequacy mode).
| Change Type | Test Requirements |
|---|
| New Service/Provider | Must have corresponding unit test |
| Modify existing logic | Existing tests pass + new logic tested |
| Bug fix | Must add regression test |
| New API endpoint | Integration test required |
| Cross-service change | E2E test required |
Test File Mapping
Use project convention from @rules/testing-project.md. If no override is defined, follow ecosystem defaults:
| Source Pattern | Test Pattern |
|---|
src/<module>/ | test/unit/<module>/ or test/<module>/ |
scripts/<name>.sh | test/scripts/<name>.test.js |
skills/<name>/SKILL.md | test/skills/<name>.test.js |
Output
- Implemented feature code + tests
- Test adequacy gate: ✅ Tests sufficient
- Review gate: ✅ Ready
- Precommit results: ✅ All Pass
Verification Checklist
Doc Sync (after precommit Pass)
⚠️ Auto-triggered by @rules/auto-loop.md — behavior-layer rule, not hook-enforced.
Only when change maps to a feature under docs/features/. Target detection uses 3-level fallback — see /update-docs for algorithm details.
precommit Pass
→ Locate feature docs (see /update-docs 3-level fallback)
→ /update-docs docs/features/<feature>/2-tech-spec.md (current-authority doc)
→ /create-request --update docs/features/<feature>/requests/<date>-<title>.md (record: status + outcome only)
→ /codex-review-doc (ONE dispatch for every doc touched above)
→ Safety valve: new code diff? → back to review loop (see /update-docs)
Sync the current-authority doc; append to the record. The tech spec states what is true now, so
code landing makes it stale and it is rewritten. A request ticket, review log or ADR states what was
decided or done at a point in time — it is updated with status and outcome, never rewritten to match
today's code, because rewriting it destroys the record. scripts/lib/doc-metadata.js decides which a
file is; /codex-review-doc reviews each under the profile that classification earns.
One /codex-review-doc for all of them, not one per file: the changed docs are a single review plan
(skills/doc-review/SKILL.md § Workflow). Per-file dispatch is what multiplied a three-file doc sync
into three whole-document reviews.
Review Loop
MUST re-review after fix until PASS (per @rules/auto-loop.md)
Review → Issues found → Fix → Re-review → ... → ✅ Pass → Next step
Examples
Input: Implement a fee calculation method
Action: /codex-architect → /codex-implement → /verify → /codex-test-review → /codex-review-fast → /precommit
Input: This code needs refactoring
Action: /simplify → /verify → /codex-test-review → /codex-review-fast → /precommit
Input: Feature dev, continue (resuming work)
Action: Check git status → identify remaining tasks → continue from current phase
