test-mdc

A test rules file for checking whether MDC files can be found and read. MDC files are configuration or instruction files used by some coding tools.

In plain words
What is it for?
Use it when testing rule discovery and retrieval, or when checking that MDC files behave like regular Markdown instruction files.
Why use it?
It helps reproduce and investigate a problem where these files are not being fetched correctly.

Cursor rule

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/4regab/agent-rules-mcp/test-mdc
Clone the repo
git clone --depth 1 https://github.com/4regab/agent-rules-mcp
Per session 59 This file is loaded in full into every session.
When invoked 59 The same file — it is already loaded in full.
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 $0.00059 $0.00059
Opus 5 $0.00030 $0.00030
Sonnet 5 $0.00012 $0.00012
Haiku 4.5 $0.00006 $0.00006

Measured 2d ago against content hash 9b91fcaad2bd, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

test-mdc 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 2d 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.

rules/test-mdc.mdc · 8 lines

What it actually says

Test MDC Rules

This is a test MDC file to reproduce the issue with .mdc files not being fetched.

Key Points

  • This should be discoverable by list_rules
  • This should be fetchable by get_rules
  • MDC files should work the same as .md files
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. 2d ago First seen · 8 lines · 59 tokens per session scan A 9b91fcaad2bd

Subscribe to this mod's changes

test-mdc is a cursor rule published in the GitHub repository 4regab/agent-rules-mcp (13 stars, last pushed 11mo ago), licensed MIT. It adds 59 tokens to every session, 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 2026-08-30.