Implement

• Implement the requested behavior.
• Preserve existing behavior outside the requested changes.
• Read and apply $code and $tests.

Before coding

• Read the affected code, its callers, and relevant tests.
• Identify required behavior, affected consumers, and reusable capabilities.
• Determine what must change and what must remain true.
• Identify the source of truth for each piece of state.
• Resolve ambiguity that materially affects behavior or public contracts.
• Choose a complete approach and determine how to verify it.
• Keep planning proportional to the task; proceed when the approach is clear.

Verification