Python Developer

---
name: python-developer
description: Implement or fix small-to-medium Python features without full SDD (FastAPI/Flask, pytest). Use for isolated Python work or when invoking /python-developer.
---

## STOP - Read before ANY tool call

1. Read `{{GUARDRAILS_PATH}}`
2. Read `_shared/sdd-artifacts/SESSION.md`; load session-state for `$Cwd`
3. If the relevant gate is not approved: **STOP** - ask user **(pt-BR)** - do **NOT** Write/Shell
4. SDD/develop skills: after **ONE** step/task, **STOP** session - handoff only
5. This skill body is **English**; user-facing prompts may be **(pt-BR)**

### Step -1 - Gate check (report in chat before continuing)

```
Gate check:
[ ] guardrails.mdc read
[ ] SESSION.md read; session-state loaded
[ ] PIPELINE.md read (SDD skills only)
[ ] User confirmed current action (sim)
-> If any unchecked: STOP
```

---

# Skill: python-developer

## Trigger

Invoke when the user asks for: `/python-developer`, `python fix`, `implement FastAPI/Flask feature`, or for **small** Python work that does not need a full PRD/PLAN cycle.

## Outcome

Working **CPython host** code and tests in the open workspace: pytest (and project lint/type checks when configured) green, on a valid feature branch, with optional commit handoff. Supports **FastAPI** and **Flask** — not a FastAPI-only skill. Does not replace SDD for multi-step or cross-repo features.

Host boundary: use this skill for CPython applications, host tools, and host tests, including tools that communicate with a board. Do not use it to recommend MicroPython device APIs, device-only modules, REPL procedures, or flashing/deployment steps.

## Lazy-load (only when needed)

| When | Path (after syncing the active adapter) |
|------|----------------------------------------|
| Repo context | `{{TOOLKIT_ROOT}}/skills/_shared/developer-common/step-0-context.md` |
| Before coding | `{{TOOLKIT_ROOT}}/skills/_shared/developer-common/step-0.5-review-guidelines.md` |
| Structure / quality (when coding) | `{{TOOLKIT_ROOT}}/skills/_shared/code-guidelines/principles/structure-and-quality.md` |
| Branching | `{{TOOLKIT_ROOT}}/rules/branch-validation.mdc`, `{{TOOLKIT_ROOT}}/skills/_shared/developer-common/step-3-branching.md` |
| Pre-commit | `{{TOOLKIT_ROOT}}/skills/_shared/developer-common/step-3.5-precommit-validation.md` |
| Commit / PR | `{{TOOLKIT_ROOT}}/skills/_shared/developer-common/step-4-commits-pr.md`, `{{TOOLKIT_ROOT}}/rules/conventional-commits.mdc` |
| Pre-PR gate | `{{TOOLKIT_ROOT}}/skills/_shared/developer-common/step-7-checklist.md` |
| FastAPI | `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/fastapi.md` |
| Flask | `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/flask.md` |
| Architecture (hub / structure) | `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/architecture.md` |
| Architecture (greenfield / style unset) | `{{TOOLKIT_ROOT}}/skills/_shared/code-guidelines/principles/architecture-selection.md` — then **one** approved style only |
| Architecture style (when ARCH names a style) | **one** of `principles/architecture/concentric-dependency.md` \| `vertical-slice.md` \| `ddd-tactical.md` \| `event-driven.md` (never glob) |
| pytest | `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/pytest.md` |
| Packaging / pyproject | `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/packaging-pyproject.md` |
| Typing | `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/typing.md` |
| Async pitfalls | `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/async-pitfalls.md` |
| Style / principles | `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/google-style.md`, `{{TOOLKIT_ROOT}}/skills/_shared/python-guidelines/principles.md` |
| Subagent-first / SPAWN.md | `{{TOOLKIT_ROOT}}/skills/_shared/developer-common/subagent-first.md`, `{{TOOLKIT_ROOT}}/skills/_shared/agents/SPAWN.md` |
| Caveman Mode (if active) | `{{TOOLKIT_ROOT}}/skills/_shared/caveman/CAVEMAN.md` - **Full cap** |
| Context pressure | `{{TOOLKIT_ROOT}}/rules/context-management.mdc` |
| Reference index (routing only) | `{{TOOLKIT_ROOT}}/skills/python-developer/reference.md` |
| Process step detail (lazy) | `{{TOOLKIT_ROOT}}/skills/python-developer/references/<section>.md` |

Do **not** preload other stack guideline packs or corporate pipeline docs. Load only the `python-guidelines` rows needed for the current task (FastAPI **and/or** Flask **and** pytest as applicable). **MUST NOT** glob `architecture/**` — load hub + **one** principles style from ARCH/CONTINUITY (brownfield: discover-first if style omitted).

**Never by default:** do not preload all `references/*.md`. do not preload other stack guideline packs. Load only Python rows needed for the current task. Do not dump full stack guideline packs or memory-bank. Load **one** section per Process step (`SKILL-REFERENCE-RETRIEVAL.md`).

## Reference routing

| Situation | Path |
|-----------|------|
| Scope / SDD escalation / design brief | `references/scope.md` |
| Implement flow | `references/execute-flow.md` |
| Must not (full) | `references/must-not.md` |

## Process

Read `references/<section>.md` for procedural detail — **not** full `reference.md`.

### Step -1b - Caveman Mode (Full cap)
1. Read `{{SDD_ROOT}}/preferences.json` (create `{ "caveman_mode": false, "caveman_level": "full" }` if missing).
2. If `caveman_mode` is false: continue without compression.
3. If true: load `{{TOOLKIT_ROOT}}/skills/_shared/caveman/CAVEMAN.md`; apply **Full** participation cap + prefs `caveman_level` (Lite skills never escalate); show once: `[Caveman] Modo ativo (respostas compactas, level={effective}). Digite caveman off para desativar.`
4. Honor `caveman on|off|status|lite|full|ultra` (and `stop caveman` / `normal mode`) during the session.
5. Auto-Clarity + never-compress gates/drafts/paths per `CAVEMAN.md`.

### 0. Scope
Follow `references/scope.md` (SDD escalation, design brief / host detection when present).

### 1. Execute
Follow `references/execute-flow.md` (subagent-first, workspace → guidelines → branch → implement → tests → handoff).

## Must not

Enforce the full list in `references/must-not.md`. Critical: no guideline dumps into children; no auto-commit; lazy-load stack guidelines only — never dump full packs or memory-bank. If runtime, target, or port evidence is missing and the answer could change between CPython and MicroPython, ask for that context before recommending an API or deployment operation; never infer device runtime from `.py` alone.

## Handoff

| Situation | Next |
|-----------|------|
| Commit | `/commit` |
| Review | `/code-review` |
| Large scope | `/sdd-spec` -> `sdd-plan` -> `sdd-develop` |
| Next PLAN step | New chat -> `/sdd-develop - PLAN/... - Step N` |