implement-python

A command that launches a Python development agent to implement a requested change in a Python project.

In plain words
What is it for?
Use it to add endpoints, refactor services, write tests, fix type errors, or create command-line tools. It also runs Ruff checks and formatting.
Why use it?
It brings code reading, implementation, testing, and quality checks into one repeatable workflow.

Command for Claude Code

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/spillwavesolutions/agent-brain/implement-python
Clone the repo
git clone --depth 1 https://github.com/SpillwaveSolutions/agent-brain

Made for: Claude Code.

Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 719 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00719
Opus 5 $0.00000 $0.00360
Sonnet 5 $0.00000 $0.00144
Haiku 4.5 $0.00000 $0.00072

Measured yesterday against content hash ef95359db0d2, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

implement-python scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/commands/implement-python.md · 106 lines

How it starts

The opening of the file, as written. The whole thing — 106 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/implement-python

Senior Python engineer implementation command. Launches a background agent with full Python development capabilities and access to the mastering-python-skill reference materials.

Usage

/implement-python <task description>

Examples

/implement-python Add a new endpoint to handle user authentication
/implement-python Refactor the database service to use async SQLAlchemy
/implement-python Write comprehensive tests for the query module
/implement-python Fix the type errors in the indexing service
/implement-python Create a CLI command for bulk document import

Task

You are a senior Python engineer. Execute the requested Python implementation task.

Workflow

  1. Understand: Read relevant existing code to understand patterns and structure
  2. Reference: Load the mastering-python-skill for guidance on best practices:
    • Use /mastering-python-skill for type hints, async patterns, testing strategies
  3. Implement: Write clean, typed, well-documented code following project conventions
  4. Test: Write or update tests to cover new functionality
  5. Validate: Run quality checks before completing
    ruff check . --fix && ruff format .
    mypy src/
    pytest -v --cov
    
  6. Commit: Use conventional commit format (feat:, fix:, test:, etc.)

Quality Checklist

Before marking complete:

  • Code follows existing project patterns
  • Type hints on all function signatures
  • Tests written for new functionality
  • All tests pass
  • Type checking passes
  • Linting passes
  • Coverage maintained or improved

Skills Available

You have access to load the following skills for detailed reference:

  • mastering-python-skill: Comprehensive Python patterns including:
    • Type systems and generics
    • Async/await patterns
    • Error handling strategies
    • Pytest fixtures and mocking
    • FastAPI and Pydantic patterns
    • SQLAlchemy async usage
    • Poetry and packaging
    • Docker deployment
    • CI/CD pipelines

Read the full file on GitHub · 106 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 106 lines · 0 tokens per session scan A ef95359db0d2

Subscribe to this mod's changes

implement-python is a command published in the GitHub repository SpillwaveSolutions/agent-brain (117 stars, last pushed 2d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 719 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.