ARR_MCP AGENTS.md

ARR_MCP AGENTS.md is an instructions file for Codex, OpenCode from GauranshMathur/ARR_MCP. It costs 2,301 tokens per session, scanned A, original, MIT.

Engineering instructions for ARR_MCP, a repository that connects services to AI clients through MCP, a standard way for applications to expose tools. They require test-driven development, API research, safe logging, conventional commit messages, and focused branches.

In plain words
What is it for?
Use them when adding or changing a service or tool, researching an external API, writing tests, preparing commits, or releasing a feature in ARR_MCP.
Why use it?
They prevent common integration failures, such as coding against an incorrect API or corrupting the JSON-RPC stream by writing logs to standard output. TDD means writing and seeing a test fail before implementing the code.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions AGENTS.md.

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 instructions/gauranshmathur/arr_mcp/agents-md
Clone the repo
git clone --depth 1 https://github.com/GauranshMathur/ARR_MCP

Made for: Codex, OpenCode.

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 ARR_MCP AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/gauranshmathur/arr_mcp/agents-md.svg)](https://agentmods.dev/instructions/gauranshmathur/arr_mcp/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/gauranshmathur/arr_mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/gauranshmathur/arr_mcp/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 2,301 This file is loaded in full into every session.
When invoked 2,301 The same file — it is already loaded in full.
Security scan A 1 finding. 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 5.1 $0.02301 $0.02301
Opus 5 $0.01151 $0.01151
Sonnet 5 $0.00460 $0.00460
Haiku 4.5 $0.00230 $0.00230

Measured 5d ago against content hash 7a5a395bf221, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

ARR_MCP AGENTS.md scanned grade A with 1 finding 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 5d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -s http://<host>:<port>/api/swagger.json | head -c 200
AGENTS.md · 137 lines

How it starts

The opening of the file, as written. The whole thing — 137 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Conventions for working in this repository. Read this before adding a service or a tool.

Non-negotiables

  1. TDD. Write the test, run it, watch it fail for the right reason, then implement. Tests written after the code prove nothing — you never saw them catch anything.
  2. Verify the API before implementing it. Never write a client from memory. See "Researching a service" below. Most of the bugs already fixed in this repo came from assuming an API shape.
  3. Never write to stdout. Under the stdio transport, stdout carries the JSON-RPC stream. A single stray fmt.Println corrupts the framing and kills the session. Logging goes to stderr; TestLoggerDefaultsToStderr pins this.
  4. Conventional commits. feat(scope):, fix(scope):, docs:, build:, ci:, test:, chore:. release-please builds the changelog from these, so the subject line is user-facing. Explain why in the body.
  5. One feature per branch, one branch per worktree. See "Worktrees".
  6. One release per feature. See "Releasing".

Researching a service

Do this in order, and stop at the first that gives an authoritative answer:

  1. Live OpenAPI/Swagger document. Some services expose one unauthenticated:
    curl -s http://<host>:<port>/api/swagger.json | head -c 200
    
    Bazarr does. Sonarr 4.x and Radarr 6.x do not — they answer 404 even with a valid key, and unauthenticated they answer 401 for every path including nonexistent ones, which disguises the 404. For those, use the upstream repo's spec and verify each endpoint against the live instance.
  2. Probe the live instance. Response schemas are often missing from the spec even when the paths are documented. When a key is needed, run the request inside the pod so the credential never leaves it:
    kubectl exec <pod> -- sh -c 'K=$(...); curl -s -H "X-API-KEY: $K" http://127.0.0.1:<port>/api/<path>'
    
  3. context7 for published library/API documentation.

Record anything surprising in the commit body. Real examples already found: Prowlarr serves /api/v1 while Sonarr and Radarr serve /api/v3; Bazarr wraps most responses in data but /badges and /system/languages are bare; provider resources (indexers, download clients, notifications) embed credentials in a fields array that must never reach a tool result.

Read the full file on GitHub · 137 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. 5d ago First seen · 137 lines · 2,301 tokens per session scan A 7a5a395bf221

Subscribe to this mod's changes

ARR_MCP AGENTS.md is an instructions file published in the GitHub repository GauranshMathur/ARR_MCP (5 stars, last pushed 6d ago), licensed MIT. It adds 2,301 tokens to every session, about $0.0115 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.