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.
git clone --depth 1 https://github.com/jondoescoding/jondoescoding-coding-rulesWrote 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.
[](https://agentmods.dev/rules/jondoescoding/jondoescoding-coding-rules/fastapi_project_structure_guide)<a href="https://agentmods.dev/rules/jondoescoding/jondoescoding-coding-rules/fastapi_project_structure_guide"><img src="https://agentmods.dev/badge/rules/jondoescoding/jondoescoding-coding-rules/fastapi_project_structure_guide/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/rules/jondoescoding/jondoescoding-coding-rules/fastapi_project_structure_guide"><img src="https://agentmods.dev/badge/rules/jondoescoding/jondoescoding-coding-rules/fastapi_project_structure_guide.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00013 | $0.01389 |
| Opus 5.5 | $0.00005 | $0.00556 |
| Sonnet 5.5 | $0.00003 | $0.00278 |
| Haiku 4.5 | $0.00001 | $0.00139 |
Grade A, and why
fastapi_project_structure_guide 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 194 lines — stays where its author put it; the contents beside it link to each section on GitHub.
FastAPI Project Structure Guide
This rule provides a comprehensive outline of a well-organized FastAPI project structure optimized for AI-powered applications with LangChain integration, vector databases, and agent-based architectures.
📁 Project Root Structure
project-root/
├── backend/ # FastAPI backend application
├── frontend/ # Frontend application (Next.js/React)
├── docs/ # Project documentation
├── scripts/ # Deployment and utility scripts
├── .env # Environment variables
├── .gitignore # Git ignore patterns
├── LICENSE # Project license
└── README.md # Project overview
🚀 Backend Structure (backend/)
Core Application Files
backend/
├── src/ # Main source code directory
├── data/ # Data files, CSVs, documents
├── docs/ # Backend-specific documentation
├── logs/ # Application logs
├── scripts/ # Backend utility scripts
├── pyproject.toml # Python project configuration
├── requirements.txt # Python dependencies
├── README.md # Backend documentation
└── start.sh # Application startup script
Source Code Organization (backend/src/)
📋 Main Entry Point
main.py- FastAPI application initialization- App configuration and metadata
- CORS middleware setup
- Router registration
- Environment-based configuration
- Lifespan event handlers
🌐 API Layer (api/)
API route definitions and endpoint handlers:
{feature}_api.py- Feature-specific API routers- Request/response models validation
- Error handling and logging
- Business logic delegation to services
- OpenAPI documentation
Example structure:
# pdf_agent_api.py
from fastapi import APIRouter, HTTPException
from ..models.chatbot import RagChatRequest, ChatResponse
from ..services.pdf_agent_service import run_retrieval_agent
router = APIRouter()
@router.post("/pdf_agent", response_model=ChatResponse)
async def rag_agent_endpoint(chat_request_body: RagChatRequest):
# Endpoint implementation
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.
- 1mo ago First seen · 194 lines · 13 tokens per session scan A 0ed7a226e548
fastapi_project_structure_guide is a cursor rule published in the GitHub repository jondoescoding/jondoescoding-coding-rules (2 stars, last pushed 2mo ago), licensed MIT. It adds 13 tokens to every session and 1,389 once invoked, about $0.0001 per session on Opus 5.5. 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.
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