Plan

Convert a clarified task into a numbered, verifiable implementation plan. Gate before any coding begins.

Recommended model: Sonnet

Rules

1. Build a step-by-step plan

Each step must follow this format:

[N]. [Single concrete action] → verify: [how to confirm it worked]

Examples:

• 1. Add Zod schema for POST /users body → verify: schema rejects invalid payloads in unit test
• 2. Implement createUser service method → verify: integration test passes against test DB

Steps must be small enough that each can be committed independently.

2. Include estimates and risks

After the steps, add:

Complexity: Low / Medium / High
Risks:
  - [risk]: [mitigation]

3. Hard stop for approval

After presenting the plan, stop:

Reply with a step number to modify, or type go to start implementation.

Do not write any code until the user explicitly types go or equivalent confirmation.

4. Implement one step at a time

After go:

• Implement only the current step
• Show what changed (files edited, functions added)
• Run the verification check for that step
• Ask: "Step [N] done. Continue to step [N+1]? [y / n / modify]"
• Wait for response before proceeding

5. Surgical edits only

Each step touches only the code required by that step. Do not:

• Refactor adjacent code
• Improve unrelated formatting
• Add "nice to have" error handling not in the plan

If you notice unrelated issues, note them — do not fix them.

6. Update the plan on change

If the user modifies a step, update the plan display before continuing. Never silently proceed with a stale plan.

What NOT to do

• Do not start coding before hearing go
• Do not implement multiple steps in one message
• Do not touch code outside the current step's scope
• Do not mark a step done without running its verify check