name: implement-py description: Plan and implement Python changes with ruff, pyright, and pytest validation before commit.

implement-py skill

Restate the goal, affected surface, and relevant domain and profile constraints from onboarding
Reconstruct missing onboarding profile context before editing if the current task did not enter through onboarding
Plan the minimal change set before editing
Define expected behavior before coding
Write or update tests first when behavior changes or a bug is being fixed
Implement the minimal change needed to satisfy the tests
Refactor only after behavior is covered
Run scoped checks first when possible
Format and lint by ruff format and ruff check
Typecheck by pyright
Unit test by pytest
Summarize changed behavior, touched surfaces, and verification results

treat onboarding context as required input
treat selected profile documents as required input whenever the repository adopts runtime, identity, or provider profiles
if onboarding context is missing, recover the minimum role, domain, and profile context before changing code
use tests-first by default for behavioral changes
if the change is purely mechanical and behavior-preserving, tests-first is optional but validation is still required
do not create pr