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/usefulsoftwareco/executor/agents-mdgit clone --depth 1 https://github.com/UsefulSoftwareCo/executorWhat 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 | $0.00624 | $0.00624 |
| Opus 5 | $0.00312 | $0.00312 |
| Sonnet 5 | $0.00125 | $0.00125 |
| Haiku 4.5 | $0.00062 | $0.00062 |
Grade A, and why
executor 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 yesterday.
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 — 59 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Executor policy
Stable contracts live here. Current setup and server mechanics are in
RUNNING.md; e2e invariants are in
e2e/AGENTS.md. Run bun run bootstrap in every fresh rift.
Verification and evidence
- Tests use Effect Vitest. Run scoped tests with
vitest run ...or the package script. Never usebun test. - Use the narrowest meaningful verification while iterating. Merge-ready gates
are
bun run format:check,lint,typecheck, andtest. - e2e is slow. Avoid running it often during development: optimize for iteration speed first, then test. Save e2e for when the change is settled, and run the narrowest scenario rather than the full suite.
- Run
bun run formatbefore a PR and include only files owned by the branch. - User-visible work requires a specific e2e run, a browsable dev instance, and the recording or trace showing what to inspect. Add a scenario when none covers the changed behavior.
Service emulators
Tests and demos that need an upstream API, OAuth/OIDC provider, or webhook use
the published @executor-js/emulate emulators rather than stubs. They provide
wire-level state, real-shaped credentials, OpenAPI descriptions, and request
ledgers. Create per-run hosted instances through the service's
/_emulate/instances control route.
Emulate is a separate project. Make emulator changes there and consume the published package here; never re-vendor or create a parallel fake inside executor.
Engineering boundaries
- Prefer correctness and predictable behavior over short-term convenience.
- Preserve runtime behavior during lint, typing, and test-structure changes.
- Use public package exports; never cross package boundaries with relative imports.
- Extract shared logic only for genuinely shared behavior. Avoid generic abstractions for one-off duplication.
- Public PRs, commits, generated files, and documentation contain no private names, internal context, customer-derived data, or AI attribution.
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.
- yesterday First seen · 59 lines · 624 tokens per session scan A 0832a83cd7e9
executor AGENTS.md is an instructions file published in the GitHub repository UsefulSoftwareCo/executor (3,466 stars, last pushed yesterday), licensed MIT. It adds 624 tokens to every session, about $0.0031 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 2026-08-30.
Other instructions, from other repositories
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
buildNext
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).
next.js AGENTS.md
Instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
spec-kit AGENTS.md
Instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
langchain AGENTS.md
Instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.