Borrowing it
Nothing to install: this file belongs to husker/a2acast. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/husker/a2acast/main/AGENTS.mdgit clone --depth 1 https://github.com/husker/a2acastWrote 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/husker/a2acast/agents-md)<a href="https://agentmods.dev/instructions/husker/a2acast/agents-md"><img src="https://agentmods.dev/badge/instructions/husker/a2acast/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.
<a href="https://agentmods.dev/instructions/husker/a2acast/agents-md"><img src="https://agentmods.dev/badge/instructions/husker/a2acast/agents-md.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00961 | $0.00961 |
| Opus 5.5 | $0.00384 | $0.00384 |
| Sonnet 5.5 | $0.00192 | $0.00192 |
| Haiku 4.5 | $0.00096 | $0.00096 |
Grade A, and why
a2acast AGENTS.md scanned grade A 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 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
`curl`-able and readable end to end. CI catches this (`stdlib_only` job, #140) and the local suite does too (`StdlibOnlyTests`); a third-party import fails before push. Stay vigilant — the test catches imports, not subtl How it starts
The opening of the file, as written. The whole thing — 71 lines — stays where its author put it; the contents beside it link to each section on GitHub.
a2acast — agent instructions
Cross-machine agent-to-agent mesh. One stdlib-only Python file (mesh.py) plus harness
integrations for Claude Code, Codex CLI, and Copilot CLI. Tests in tests/test_mesh.py.
These rules exist because they were learned the expensive way. Read them before writing code, not after.
Hard constraints
mesh.pyis stdlib-only. No third-party imports, ever. It is meant to becurl-able and readable end to end. CI catches this (stdlib_onlyjob, #140) and the local suite does too (StdlibOnlyTests); a third-party import fails before push. Stay vigilant — the test catches imports, not subtle misuse of a stdlib facility.- Python 3.8+.
requires-python = ">=3.8". Nomatchstatements, noX | Yunions evaluated at runtime, no 3.9+ stdlib. - Tests:
python3 -m unittest discover -s tests(pythonon Windows)
Writing security-relevant code
Anything touching crypto, identity, pins, certs, revocation, verdicts, or the wire format is security-relevant. So is anything on a #62 / #74 / #76 / #93 line.
-
Never claim a property you have not tested. A PR body is a hypothesis, not evidence. On 2026-07-25 three PRs in one batch each shipped a confident description asserting the exact property its code lacked — a rename guard that left both known seams open, a rollout gate that was send-side against a receive-side hazard, and a non-suppressibility mechanism that inverted into a suppression primitive. All three were caught only by reviewers reading the code. Write what the code does. If a guard is partial, say which case it misses.
-
Every security fix ships a test that fails without it. Not a test that passes with it — one that fails when the fix is reverted.
-
A guard must be load-bearing in both directions. Revert the fix: the attack test must fail. Disable the mechanism entirely: the legitimate-use test must fail. A guard that only ever blocks is a guard you can delete.
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 · 71 lines · 961 tokens per session scan A 12ba4d730643
a2acast AGENTS.md is an instructions file published in the GitHub repository husker/a2acast (8 stars, last pushed 2mo ago), licensed MIT. It adds 961 tokens to every session, about $0.0038 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other instructions, from other repositories
vscode buildNext.instructions.md
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
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, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
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.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deno copilot-instructions.md
Copilot instructions for denoland/deno, covering deno development guide for github copilot, network access, high level overview, key directories and key files to understand first.