Invoke Python Engineer

Implement Python Skill

This direct-use wrapper delegates Python implementation work to the python-typed-engineer worker. Use this entry point when a prompt needs a scoped Python change that must stay inside the typed engineer's guardrails.

When to Use This Skill

Use this skill when:

• The user requests a Python code change, bug fix, refactor, or test addition.
• Estimated scope fits the small path (1-3 production files plus corresponding tests).
• The toolchain (Black, Ruff, Pyright, Pytest) can be run in the current environment, or the user has explicitly authorized an unverified plan-only response.

If the estimated scope exceeds the small-path budget, this skill defers to the orchestrated flow via python-change-budget-router instead of proceeding directly.

Inputs

• Objective statement (what the change must accomplish).
• Files or entrypoints in scope.
• Constraints, including public APIs that must be preserved.
• Optional approved plan. If none is supplied, the worker delegates plan authoring to atomic_planner before any edits.
• Optional budget override in the form budget: prod=<N>, test=<M> subject to repo policy compliance.

Output Paths

• Python source and test files within the approved scope.
• Baseline evidence under <FEATURE>/evidence/baseline/<timestamp>/ and post-change evidence under <FEATURE>/evidence/qa-gates/<timestamp>/ per evidence-and-timestamp-conventions.
• This location is canonical per evidence-and-timestamp-conventions and is not overridable. See .claude/skills/evidence-and-timestamp-conventions/SKILL.md for the canonical evidence path authority.
• Plan artifacts under the active feature folder when the task is feature-scoped.

Required Reporting Block

The worker must return the python-qa-gate reporting block:

1. Scope (exact file list).
2. Baseline (Ruff, Pyright, Pytest, coverage status).
3. Plan (design and test strategy).
4. Diffs (patch-style or full-file replacements).
5. QA Gate Results (Ruff, Pyright, Pytest, and coverage deltas, or clearly marked unverified).

Worker Routing

• Worker: python-typed-engineer

Preloaded Contracts

The worker operates under the following preloaded skills and rules:

• policy-compliance-order
• python-change-budget-router
• atomic-plan-contract
• python-qa-gate
• acceptance-criteria-tracking
• feature-promotion-lifecycle
• remediation-handoff-atomic-planner
• evidence-and-timestamp-conventions
• .claude/rules/python.md (path-scoped for **/*.py)
• .claude/rules/general-code-change.md
• .claude/rules/general-unit-test.md
• .claude/rules/tonality.md