11-prompt-maintainer

11-prompt-maintainer is a cursor rule for Cursor from MarcoPorcellato/matryca-plumber. It costs 14 tokens per session (454 once invoked), scanned A, original, Apache-2.0.

A maintenance checklist for changing prompt-building code, agent instruction files, and MCP tool descriptions. It lists the related files, required checks, and documentation updates.

In plain words
What is it for?
Use it when editing prompt builders, agent fragments, MCP tool docstrings, or prompt hash snapshots. It also explains which build, test, language, and commit checks to run.
Why use it?
It reduces the risk of changing generated system instructions incorrectly or leaving prompt snapshots and documentation out of sync.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/. Also seen: mentions AGENTS.md.

Good fit Use it when editing prompt builders, agent fragments, MCP tool docstrings, or prompt hash snapshots. It also explains which build, test, language, and commit checks to run.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/marcoporcellato/matryca-plumber/11-prompt-maintainer
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.

Clone the repo
git clone --depth 1 https://github.com/MarcoPorcellato/matryca-plumber

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 11-prompt-maintainer

README.md
[![agentmods](https://agentmods.dev/badge/rules/marcoporcellato/matryca-plumber/11-prompt-maintainer/github.svg)](https://agentmods.dev/rules/marcoporcellato/matryca-plumber/11-prompt-maintainer)
Your own site
<a href="https://agentmods.dev/rules/marcoporcellato/matryca-plumber/11-prompt-maintainer"><img src="https://agentmods.dev/badge/rules/marcoporcellato/matryca-plumber/11-prompt-maintainer/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.

agentmods 80×15 button for 11-prompt-maintainer

Your own site · 80×15
<a href="https://agentmods.dev/rules/marcoporcellato/matryca-plumber/11-prompt-maintainer"><img src="https://agentmods.dev/badge/rules/marcoporcellato/matryca-plumber/11-prompt-maintainer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 14 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 454 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00014 $0.00454
Opus 5 $0.00007 $0.00227
Sonnet 5 $0.00003 $0.00091
Haiku 4.5 $0.00001 $0.00045

Measured 9d ago against content hash d407854efb05, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

11-prompt-maintainer 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 9d 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.

.cursor/rules/11-prompt-maintainer.mdc · 28 lines

What it actually says

Prompt maintainer checklist (Matryca Plumber)

Load on demand when editing Tier-1 prompts, docs/openspec/agent/ fragments, or MCP tool contracts.

Rule routing: Complements 06-auto-changelog.mdc, 07-env-example.mdc, AGENTS.md.

Trigger → Azione

Hai modificato Devi eseguire
docs/openspec/agent/*.md make build-system-prompt && make check-system-prompt
src/agent/**/prompts.py, src/graph/**/prompts.py (builder Tier-1A) uv run pytest tests/test_daemon_prompts.py --update-prompt-hashesgit add tests/prompt_hash_snapshots.json
src/agent/**/prompts.py (builder Tier-1B writer) Come sopra + verifica che nessuna stringa contenga English only
mcp_server.py (docstrings tool) Aggiorna docs/openspec/agent/mcp-tools.md (+ tool-reference.md se serve) → make build-system-prompt; alla release MCP sync anche llms.txt §2
tests/prompt_hash_snapshots.json Il commit message deve contenere prompt(<builder>): <motivo>

Non fare

  • Non editare SYSTEM_PROMPT.md direttamente — è generato (<!-- GENERATED — do not edit -->).
  • Non aggiungere frammenti docs/openspec/agent/*.md senza riga in _assembly_order.txtmake check-system-prompt fallisce.
  • Non aggiungere stringhe system inline in llm_client.py — usa un builder di dominio che importa solo src/agent/prompts/core.py.
  • Non impostare alwaysApply: true su nuove rule senza approvazione esplicita.
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. 9d ago First seen · 28 lines · 14 tokens per session scan A d407854efb05

Subscribe to this mod's changes

11-prompt-maintainer is a cursor rule published in the GitHub repository MarcoPorcellato/matryca-plumber (97 stars, last pushed today), licensed Apache-2.0. It adds 14 tokens to every session and 454 once invoked, about $0.0001 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 2026-08-30.