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/e-gov/cursor-promptsWrote 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/e-gov/cursor-prompts/fastapi-specific)<a href="https://agentmods.dev/rules/e-gov/cursor-prompts/fastapi-specific"><img src="https://agentmods.dev/badge/rules/e-gov/cursor-prompts/fastapi-specific/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/e-gov/cursor-prompts/fastapi-specific"><img src="https://agentmods.dev/badge/rules/e-gov/cursor-prompts/fastapi-specific.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 | $0.02182 | $0.02182 |
| Opus 5.5 | $0.00873 | $0.00873 |
| Sonnet 5.5 | $0.00436 | $0.00436 |
| Haiku 4.5 | $0.00218 | $0.00218 |
Grade A, and why
fastapi-specific 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 — 135 lines — stays where its author put it; the contents beside it link to each section on GitHub.
FastAPI-Specific Standards
Rule stack (use in this order for new work)
mdc:rules/common/security.mdc,mdc:rules/common/integration-standards.mdc,mdc:rules/common/component-technical-standards.mdc,mdc:rules/common/agent-memory.mdc— policy, integration shape, component constraints, project memory.- This file — FastAPI/Pydantic layout, contract generation, errors, lifecycle.
mdc:rules/python-fastapi/python-documentation-standards.mdc— lean docstrings (only non-obvious behavior); deslop-aligned defaults.mdc:rules/python-fastapi/sqlalchemy-data-access.mdc,mdc:rules/python-fastapi/application-logging.mdc,mdc:rules/python-fastapi/audit-logging.mdc— DB queries,structlog,AuditLogger.AGENTS.md— commands, triggers, repo layout.
Scope
- This rule applies to FastAPI backend work in repositories that adopt these conventions.
- Keep guidance practical, concise, and production-oriented.
- Application logging, audit logging, and SQLAlchemy access:
mdc:rules/python-fastapi/application-logging.mdc,mdc:rules/python-fastapi/audit-logging.mdc,mdc:rules/python-fastapi/sqlalchemy-data-access.mdc.
Common rules (do not contradict; language-agnostic policy lives here)
mdc:rules/common/security.mdc— input validation, auth/session/token rules, error messages, security logging expectations, dependency hygiene.mdc:rules/common/integration-standards.mdc— REST resource design, HTTP methods/status codes, RFC 7807 errors, OpenAPI contract-first, pagination at the API, correlation/trace headers for integrations.mdc:rules/common/component-technical-standards.mdc— UTF-8, layered architecture, Alembic migrations (not on every startup), stateless service, env-based config, integration tests, JSON logs with correlation (conceptually), graceful shutdown / long-running job patterns.mdc:rules/common/agent-memory.mdc— read/updatedocs/agent-memory.md.
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 · 135 lines · 2,182 tokens per session scan A 8a58e1c116c9
fastapi-specific is a cursor rule published in the GitHub repository e-gov/cursor-prompts (34 stars, last pushed 6mo ago), licensed MIT. It adds 2,182 tokens to every session, about $0.0087 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 2026-08-30.
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python-conventions
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