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.
npx agentmods add instructions/narumiruna/aru/agents-mdgit clone --depth 1 https://github.com/narumiruna/aruWrote 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/instructions/narumiruna/aru/agents-md)<a href="https://agentmods.dev/instructions/narumiruna/aru/agents-md"><img src="https://agentmods.dev/badge/instructions/narumiruna/aru/agents-md.svg" alt="Measured on agentmods" 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 | $0.01055 | $0.01055 |
| Opus 5 | $0.00528 | $0.00528 |
| Sonnet 5 | $0.00211 | $0.00211 |
| Haiku 4.5 | $0.00105 | $0.00105 |
Grade A, and why
aru AGENTS.md 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 3d 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 — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Repository Guidance
Scope and Authority
This file applies to the entire repository.
Add a nested AGENTS.md only when a subtree has materially different rules.
For explanation, review, diagnosis, or planning requests, inspect and report without changing files.
For requested implementation or documentation work, make bounded local changes and run proportionate non-destructive checks.
Do not push, open or merge pull requests, create tags, dispatch workflows, publish releases, use aru's destructive --force takeover, or materially expand scope unless explicitly requested.
Communication & Documentation
- Lead with the most important relevant information and omit anything unnecessary or repeated.
- Use clear structure, familiar words, and concise sentences.
- Explain the main idea simply before adding necessary detail.
- Keep information accurate.
- Make documented rules specific and verifiable.
- In documentation, put each prose sentence on its own source line.
- Draw diagrams using Mermaid syntax.
Code Style
- Follow KISS (Keep It Simple) and YAGNI (You Aren't Gonna Need It).
- Prefer simple, minimal solutions over unnecessary complexity.
- Split source files over 1,000 lines along clear responsibility boundaries, or document why they must remain intact.
Project Map
src/cli.rsdefines the Clap command contract.src/app.rsandsrc/app/orchestrate commands.src/manifest.rsandsrc/lockfile.rsown persisted formats.src/resolver.rs,src/registry.rs, andsrc/source/resolve package inputs.src/target/owns target-specific projections.- Keep target capability differences in
src/target/instead of scattering target checks through orchestration code. src/instruction/,src/skill.rs, andsrc/sync.rsimplement discovery and reconciliation.src/ownership.rsandsrc/transaction.rsprotect user content and atomic multi-file updates.tests/*.rsexercise the public CLI.tests/fixtures/contracts/contains byte-stable format fixtures.- Registry and instruction fixtures live under their corresponding fixture directories.
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.
- 3d ago First seen · 94 lines · 1,055 tokens per session scan A 0642111df1ee
aru AGENTS.md is an instructions file published in the GitHub repository narumiruna/aru (5 stars, last pushed 10d ago), licensed MIT. It adds 1,055 tokens to every session, about $0.0053 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 2026-08-31.
Other instructions, from other repositories
apm tests.instructions.md
Test conventions: URL assertions must use urllib.parse, never substring.
apm cli.instructions.md
CLI Design Guidelines for visual output, styling, and user experience standards.
apm integrators.instructions.md
Architecture rules for file-level integrators (BaseIntegrator pattern).
apm copilot-instructions.md
Copilot instructions for microsoft/apm, covering linting (canonical contract), ci-mirror commands, local workflow, common surprises and lifecycle binding.
apm architecture.instructions.md
Single canonical owner discipline: one authority per durable decision, guarded by a regression test + a static boundary check.
apm cicd.instructions.md
CI/CD Pipeline configuration for PyInstaller binary packaging and release workflow.