scout_apm_mcp.rb: Instructions file for Codex

AGENTS.md

scout_apm_mcp.rb AGENTS.md is an instructions file for Codex, OpenCode from amkisko/scout_apm_mcp.rb. It costs 4,137 tokens per session, scanned C, original, MIT.

Project instructions for a Ruby service that connects to Scout APM, a tool for monitoring application performance. They also define shared guidance managed through Pray, a system for distributing team instructions.

In plain words
What is it for?
Changing or refactoring the service, updating shared agent instructions, and checking work with the project's planning, application, verification, and test commands.
Why use it?
They help contributors follow the project's required workflow and avoid editing generated files that will be overwritten. They require tests to demonstrate bugs and behavior changes before code is shipped.

Instructions file for CodexOpenCode

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

This is amkisko/scout_apm_mcp.rb's own configuration. It tells Codex and OpenCode how to work on scout_apm_mcp.rb itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything scout_apm_mcp.rb configures →

Reuse

Borrowing it

Nothing to install: this file belongs to amkisko/scout_apm_mcp.rb. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/amkisko/scout_apm_mcp.rb/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/amkisko/scout_apm_mcp.rb

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 scout_apm_mcp.rb AGENTS.md

README.md
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Your own site
<a href="https://agentmods.dev/instructions/amkisko/scout_apm_mcp.rb/agents-md"><img src="https://agentmods.dev/badge/instructions/amkisko/scout_apm_mcp.rb/agents-md/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 scout_apm_mcp.rb AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/amkisko/scout_apm_mcp.rb/agents-md"><img src="https://agentmods.dev/badge/instructions/amkisko/scout_apm_mcp.rb/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 4,137 This file is loaded in full into every session.
When invoked 4,137 The same file — it is already loaded in full.
Security scan C 1 finding. 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 $0.04137 $0.04137
Opus 5 $0.02069 $0.02069
Sonnet 5 $0.00827 $0.00827
Haiku 4.5 $0.00414 $0.00414

Measured today against content hash c5dc18b146f8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade C, and why

scout_apm_mcp.rb AGENTS.md scanned grade C 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 today.

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.

Hidden instructionshighPrompt injection

Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.

<!-- pray:0 ignore-comments -->
AGENTS.md · 265 lines

How it starts

The opening of the file, as written. The whole thing — 265 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent context

Do not edit managed blocks in AGENTS.md or provisioned files under .agents/. To change shared guidance, update Prayfile and run pray install.

Shared instructions

  • when fixing or refactoring code, add or update tests first to expose the current bug/regression path (or missing contract), then implement the fix, then run focused and broader checks, and do not ship behavior changes without proving before/after via specs;
  • test only executable logic and user-facing behavior; tests should affect coverage metrics;
  • avoid tests that only assert implementation details; avoid file/page content/ordering/regex assertions; avoid duplicating tests;
  • user interface texts should never mention implementation technical details;
  • prefer files around <=150 LOC when cohesion allows, but never split coherent logic purely to satisfy line count; split only when it improves ownership, readability, and reviewability;
  • do not use abbreviations and short names for variables, methods, classes, etc. unless it is a very common abbreviation or short name;
  • avoid explanatory comments, but allow intent comments for non-obvious constraints, invariants, concurrency edges, or external contract requirements;
  • keep the idea that code reflects user experience, so readability, structure, and clarity are product qualities;
  • pull request description should include answers to questions: what problem is solved, why it matters, how the solution works, and any relevant context; if the change is non-trivial, include reproduction steps or a changelog entry with intent;
  • pull request checklist: changelog entry with intent or reproduction steps when relevant, test coverage, and quality checks done;
  • follow docs-conventions for usr/docs trace filenames and layout;
  • report completed actions only with observed evidence; validation output must list exact commands run and observed results;
  • ignore style-only dust unless it harms correctness, operability, maintainability, or auditability under realistic load;
  • fix the cause of a race, not a retry around it; prefer positive names; compute at write when a read cannot paginate; do not change production design only so tests can reach it.

Read the full file on GitHub · 265 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. today Changed · -16 tokens per session c5dc18b146f8
  2. 3d ago Changed · +139 lines · +2,721 tokens per session 644b069d8ad5
  3. 9d ago First seen · 126 lines · 1,432 tokens per session scan C a1e7352a5b19

Subscribe to this mod's changes

scout_apm_mcp.rb AGENTS.md is an instructions file published in the GitHub repository amkisko/scout_apm_mcp.rb (2 stars, last pushed today), licensed MIT. It adds 4,137 tokens to every session, about $0.0207 per session on Opus 5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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