tools AGENTS.md

A project instruction file for the avifenesh/tools repository, a TypeScript library of tools used by language-model coding agents. It explains the repository's architecture, testing expectations, and working rules.

In plain words
What is it for?
Use it when working on the repository's agent tools, such as Read, Write, Grep, and Glob, to understand its monorepo structure, testing approach, technology choices, and contribution rules.
Why use it?
It gives coding agents the context needed to change this repository safely, where tool behavior is judged by how well language models choose and interpret the tools. It also records the project's operational conventions.

Instructions file for CodexOpenCode

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/avifenesh/tools/agents-md
Clone the repo
git clone --depth 1 https://github.com/avifenesh/tools

Made for: Codex, OpenCode.

Per session 1,661 This file is loaded in full into every session.
When invoked 1,661 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 $0.01661 $0.01661
Opus 5 $0.00830 $0.00830
Sonnet 5 $0.00332 $0.00332
Haiku 4.5 $0.00166 $0.00166

Measured 2d ago against content hash 63c9c8ab2e52, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

tools 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 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

AGENTS.md · 120 lines

How it starts

The opening of the file, as written. The whole thing — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md — @agent-sh/harness-* monorepo

Guidance for Codex working on this repo. The repo builds LLM-facing agent tools (Read, Write, Grep, Glob, ...) as a TypeScript-first npm library, with Rust ports coming later. The tools are consumed by real language models inside agent harnesses — not by deterministic callers.

The prime directive: treat LLM tools as a chaotic distributed system, not as kernel code

The user is a systems software engineer (Valkey, CRIU, ElastiCache). These tools look like regular functions — typed inputs, typed outputs, clean error enums — but that framing is a trap. The consumer is a probabilistic model, so the contract is not "given these args, produce this output." The contract is:

Given only the tool's textual surface (name, description, schema field names, error messages, output shape, pagination hints), does a real model, across many families (Qwen, Llama, GPT, Codex, DeepSeek), pick this tool, call it correctly, interpret the result, and make good next moves — without giving up and falling back to Bash?

That is the spec. Everything else is implementation detail.

Why this matters — the failure modes that unit tests never catch

  1. Description-driven misuse. An ambiguous parameter name (path vs file_path, limit vs max_lines) causes the model to pass the wrong thing. The code is fine. The tool is broken.
  2. Unrecoverable errors. ENOENT with no context leaves the model stuck. A NOT_FOUND that lists sibling candidates lets it self-correct.
  3. Ignored hints. The output says next_offset: 2000 but the model re-reads from 0 and loops. The pagination design is the failure.
  4. Silent non-invocation. The model reads the description, decides the tool doesn't fit, and shells out to cat / grep / ls via Bash instead. You will not see this in any unit test. You will only see it when you log real sessions and notice your tool is never called.
  5. Hallucinated output. The tool returns JSON the model misparses, so the model confidently reports content that was never in the file.
  6. Tool-as-friction. A well-intentioned safety rail (sensitive-path deny, forced pagination, mandatory ledger confirmation) makes the tool annoying enough that the model routes around it. The user has shipped many tools and watched exactly this happen — "too many to count."

Read the full file on GitHub · 120 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. 2d ago First seen · 120 lines · 1,661 tokens per session scan A 63c9c8ab2e52

Subscribe to this mod's changes

tools AGENTS.md is an instructions file published in the GitHub repository avifenesh/tools (5 stars, last pushed 3d ago), licensed MIT. It adds 1,661 tokens to every session, about $0.0083 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.