python

This document provides comprehensive guidance for Python development in Crescendo Lab, covering architecture patterns, coding style, and best practices for FastAPI applications.

Cursor rule for Cursor

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/chatbotgang/ai-coding-workshop-250712/python
Clone the repo
git clone --depth 1 https://github.com/chatbotgang/ai-coding-workshop-250712

Made for: Cursor.

Per session 5,675 This file is loaded in full into every session.
When invoked 5,675 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.05675 $0.05675
Opus 5 $0.02838 $0.02838
Sonnet 5 $0.01135 $0.01135
Haiku 4.5 $0.00568 $0.00568

Measured today against content hash ba0eb3bc6e96, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

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 today.

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.

.cursor/rules/python.mdc · 873 lines

How it starts

The opening of the file, as written. The whole thing — 873 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Python Development Guide in CL

This document provides comprehensive guidance for Python development in Crescendo Lab, covering architecture patterns, coding style, and best practices for FastAPI applications.

Table of Contents

Architecture Patterns

Clean Architecture

Python projects in CL follow a clean architecture pattern with distinct layers:

  1. Entrypoint Layer (entrypoint/)

    • Contains application entry points and configuration
    • HTTP servers, CLI commands, and application bootstrapping
    • Depends on router and domain layers
  2. Domain Layer (internal/domain/)

    • Contains business entities and logic
    • Independent of external frameworks and databases
    • Defines protocols (interfaces) that are implemented by outer layers
  3. Router Layer (internal/router/)

    • HTTP handlers, middleware, and routing logic
    • Connects external HTTP requests to internal domain logic
    • Depends on domain layer
  4. Adapter Layer (internal/adapter/) - Future implementation

    • Implements protocols defined in the domain layer
    • Connects the application to external systems (databases, message brokers, etc.)
    • Contains concrete implementations of repositories and services

Read the full file on GitHub · 873 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. today First seen · 873 lines · 5,675 tokens per session scan A ba0eb3bc6e96

Subscribe to this mod's changes

python is a cursor rule published in the GitHub repository chatbotgang/ai-coding-workshop-250712 (66 stars, last pushed 1y ago), licensed Apache-2.0. It adds 5,675 tokens to every session, about $0.0284 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 2026-09-01.