Implementing Features

Step 2: Scope Check

Verify the feature is small batch (max 5-10 files). If larger, break into smaller features first and confirm with user.

Step 3: Start WIP Tracking

bash .agentic/tools/wip.sh start F-XXXX "Description" "file1 file2"

This creates .agentic-state/WIP.md — a lock that prevents premature commits.

Step 4: Implement

1. Read and understand acceptance criteria fully
2. Check CONTEXT_PACK.md for "Where to look first"
3. Check STACK.md for development_mode (standard or tdd)
4. Implement in small increments:
   • Write code following references/programming_standards.md
   • Add tests that verify acceptance criteria
   • Run tests after each significant change
5. Checkpoint progress periodically:

   bash .agentic/tools/wip.sh checkpoint "Completed step X"
   

Step 5: Checkpoint Validation (priority-grouped ACs)

When acceptance criteria have priority groups (P1/P2):

1. Complete all P1 ACs first
2. Run tests for P1 group
3. Report to user: "P1 complete — core feature works. Proceed to P2?"
4. Only proceed to P2 after user confirmation

This ensures MVP is solid before adding enhancements.

Step 6: Verify Before Declaring Done

• All acceptance criteria met (P1 at minimum, P2 if confirmed)
• Tests pass
• No unrelated files changed
• Code follows project conventions

Then hand off to the committing-changes workflow (do NOT commit directly).

Examples

Example 1: Implementing a new CLI command User says: "Add an ag sync command" Steps taken:

1. Check spec/acceptance/F-0125.md exists — it does, read criteria
2. Start WIP: wip.sh start F-0125 "ag sync command" "ag .agentic/tools/sync.sh"
3. Read CONTEXT_PACK.md, find existing ag commands in ag script
4. Implement sync.sh following existing tool patterns
5. Add test in tests/
6. Checkpoint: wip.sh checkpoint "sync.sh working, tests pass" Result: Feature implemented, tests passing, ready for commit workflow.

Example 2: User describes functionality without a feature ID User says: "Build a dark mode toggle" Steps taken:

1. No F-XXXX exists — create F-0150 in spec/FEATURES.md
2. Draft acceptance criteria, show to user for approval
3. Create spec/acceptance/F-0150.md
4. Start WIP, implement, test Result: Feature tracked from spec through implementation.

Troubleshooting

Error: wip.sh exits "WIP already active" Cause: Previous work was interrupted or not completed. Solution: Run bash .agentic/tools/wip.sh check to see what's in progress. Either complete it (wip.sh complete) or abandon it (wip.sh abandon) before starting new work.

Error: No acceptance criteria found Cause: Feature work attempted without spec. Solution: Create spec/acceptance/F-XXXX.md first. Use the template at .agentic/spec/acceptance.template.md.

Error: Scope too large (>10 files) Cause: Feature is too big for one batch. Solution: Break into 3-5 smaller features, each touching max 5-10 files. Confirm decomposition with user.

References

• For implementation checklist: see references/feature_implementation.md
• For pre-implementation gates: see references/feature_start.md
• For code standards: see references/programming_standards.md