What is dev AGENTS.md?

Project instructions for a Rust codebase, including commands for building, testing, checking, linting, and formatting. They also record project-specific rules and lessons about how parts of the code work.

Use them when developing in the project, running its verification commands, managing dependencies, and working with its development-container code.

They give contributors a reliable way to validate changes and avoid known mistakes in the repository.

How squirrelsoft-dev/dev configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to squirrelsoft-dev/dev. 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/squirrelsoft-dev/dev/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/squirrelsoft-dev/dev

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/squirrelsoft-dev/dev/agents-md/github.svg)](https://agentmods.dev/instructions/squirrelsoft-dev/dev/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/squirrelsoft-dev/dev/agents-md"><img src="https://agentmods.dev/badge/instructions/squirrelsoft-dev/dev/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/squirrelsoft-dev/dev/agents-md"><img src="https://agentmods.dev/badge/instructions/squirrelsoft-dev/dev/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 518 This file is loaded in full into every session.

When invoked 518 The same file — it is already loaded in full.

Security scan A 0 findings. 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.

Model	Per session	Once invoked
Fable 5.1	$0.00518	$0.00518
Opus 5.5	$0.00207	$0.00207
Sonnet 5.5	$0.00104	$0.00104
Haiku 4.5	$0.00052	$0.00052

Measured 1mo ago against content hash 17654e374360, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

dev 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 1mo 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.

AGENTS.md · 41 lines

How it starts

The opening of the file, as written. The whole thing — 41 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Project Commands

Install: cargo build
Build: cargo build --release
Test: cargo test
Lint: cargo clippy --all-targets -- -D warnings
Format check: cargo fmt --all --check
Typecheck: cargo check

Non-Negotiables

Do not add new dependencies without a strong reason
Always include verification steps after code changes
Run tests before marking any task complete

Common Mistakes

(add rules here as you discover repeated issues)

Learnings

The devcontainer crate's tests are all in-file #[cfg(test)] mod tests; it has no tests/ directory (the vendored crates/buildkit-client-patch is the exception).
Anything that reads ~/.dev has an *_in variant taking a &DevHome (defined in src/util/paths.rs); test against those with DevHome::at(tmp) rather than the current()-based wrappers.
In src/devcontainer/merge.rs, array merge strategy is split: forwardPorts/mounts concatenate with dedup (merge_array), but runArgs concatenates without dedup (merge_array_concat) because repeated flags like --env-file are legitimate and order matters. Don't move runArgs back into the dedup path.
runArgs is translated in src/devcontainer/run_args.rs (supported create-time subset: env file/env flags plus --cap-add, --security-opt, --userns, --privileged, --init) and applied in src/commands/up.rs before container creation. Every other flag is rejected before side effects. Docker/Podman use the shared bollard create body; Apple accepts only the env subset. Compose rejects project-declared runArgs but ignores inherited lower-layer runArgs. extra_args on ContainerConfig is now always empty (kept for struct compatibility).

Maintaining this file

Keep this file for knowledge useful to almost every future agent session in this project. Do not repeat what the codebase already shows; point to the authoritative file or command instead. Prefer rewriting or pruning existing entries over appending new ones. When updating this file, preserve this bar for all agents and keep entries concise.

Read the full file on GitHub · 41 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.

1mo ago First seen · 41 lines · 518 tokens per session scan A 17654e374360

Subscribe to this mod's changes

dev AGENTS.md is an instructions file published in the GitHub repository squirrelsoft-dev/dev (17 stars, last pushed 4d ago), licensed MIT. It adds 518 tokens to every session, about $0.0021 per session on Opus 5.5. 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 2026-09-01.

Languages Rust Testing

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Copilot instructions for Rheosoph/flow-like, covering flow-like wasm node development — rust, project overview, build & test, architecture and pin types.

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Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

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