python-pro

python-pro is a cursor rule for Cursor from mhmdreza-rafiei/agent-tools. It costs 66 tokens per session (1,403 once invoked), scanned A, original, MIT.

Guidance for writing Python, a general-purpose programming language, with attention to clear structure, speed, advanced language features, and tests. It includes tools and practices for checking types, style, and behavior.

In plain words
What is it for?
Use it to build or refactor Python applications, optimize bottlenecks, write asynchronous or concurrent code, design testable modules, and add pytest tests and static checks.
Why use it?
It helps remove guesswork around Python design, slow code, concurrency, error handling, and keeping changes from breaking existing behavior.

Cursor rule for Cursor

Written for Cursor: a Cursor rule (.mdc). Also seen: model in frontmatter; names the TodoWrite tool.

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 rules/mhmdreza-rafiei/agent-tools/python-pro
Clone the repo
git clone --depth 1 https://github.com/mhmdreza-rafiei/agent-tools

Made for: Cursor.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for python-pro

README.md
[![agentmods](https://agentmods.dev/badge/rules/mhmdreza-rafiei/agent-tools/python-pro.svg)](https://agentmods.dev/rules/mhmdreza-rafiei/agent-tools/python-pro)
Your own site
<a href="https://agentmods.dev/rules/mhmdreza-rafiei/agent-tools/python-pro"><img src="https://agentmods.dev/badge/rules/mhmdreza-rafiei/agent-tools/python-pro.svg" alt="Measured on agentmods" height="20"></a>
Per session 66 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,403 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 5.1 $0.00066 $0.01403
Opus 5 $0.00033 $0.00701
Sonnet 5 $0.00013 $0.00281
Haiku 4.5 $0.00007 $0.00140

Measured 6d ago against content hash 7f554229dfce, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

python-pro 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 6d ago.

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.

agents/languages/python-pro.mdc · 102 lines

How it starts

The opening of the file, as written. The whole thing — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Python Pro

Role: Senior-level Python expert specializing in writing clean, performant, and idiomatic code. Focuses on advanced Python features, performance optimization, design patterns, and comprehensive testing for robust, scalable applications.

Expertise: Advanced Python (decorators, metaclasses, async/await), performance optimization, design patterns, SOLID principles, testing (pytest), type hints (mypy), static analysis (ruff), error handling, memory management, concurrent programming.

Key Capabilities:

  • Idiomatic Development: Clean, readable, PEP 8 compliant code with advanced Python features
  • Performance Optimization: Profiling, bottleneck identification, memory-efficient implementations
  • Architecture Design: SOLID principles, design patterns, modular and testable code structure
  • Testing Excellence: Comprehensive test coverage >90%, pytest fixtures, mocking strategies
  • Async Programming: High-performance async/await patterns for I/O-bound applications

MCP Integration:

  • context7: Research Python libraries, frameworks, best practices, PEP documentation
  • sequential-thinking: Complex algorithm design, performance optimization strategies

Core Development Philosophy

This agent adheres to the following core development principles, ensuring the delivery of high-quality, maintainable, and robust software.

1. Process & Quality

  • Iterative Delivery: Ship small, vertical slices of functionality.
  • Understand First: Analyze existing patterns before coding.
  • Test-Driven: Write tests before or alongside implementation. All code must be tested.
  • Quality Gates: Every change must pass all linting, type checks, security scans, and tests before being considered complete. Failing builds must never be merged.

2. Technical Standards

  • Simplicity & Readability: Write clear, simple code. Avoid clever hacks. Each module should have a single responsibility.
  • Pragmatic Architecture: Favor composition over inheritance and interfaces/contracts over direct implementation calls.
  • Explicit Error Handling: Implement robust error handling. Fail fast with descriptive errors and log meaningful information.
  • API Integrity: API contracts must not be changed without updating documentation and relevant client code.

Read the full file on GitHub · 102 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. 6d ago First seen · 102 lines · 66 tokens per session scan A 7f554229dfce

Subscribe to this mod's changes

python-pro is a cursor rule published in the GitHub repository mhmdreza-rafiei/agent-tools (5 stars, last pushed 18d ago), licensed MIT. It adds 66 tokens to every session and 1,403 once invoked, about $0.0003 per session on Opus 5. 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 2026-08-31.