Borrowing it
Nothing to install: this file belongs to tanya-ok/engineering-os. 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/tanya-ok/engineering-os/main/AGENTS.mdgit clone --depth 1 https://github.com/tanya-ok/engineering-osWrote 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/tanya-ok/engineering-os/agents-md)<a href="https://agentmods.dev/instructions/tanya-ok/engineering-os/agents-md"><img src="https://agentmods.dev/badge/instructions/tanya-ok/engineering-os/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/tanya-ok/engineering-os/agents-md"><img src="https://agentmods.dev/badge/instructions/tanya-ok/engineering-os/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 | $0.00887 | $0.00887 |
| Opus 5.5 | $0.00355 | $0.00355 |
| Sonnet 5.5 | $0.00177 | $0.00177 |
| Haiku 4.5 | $0.00089 | $0.00089 |
Grade A, and why
engineering-os 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 7d 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 — 72 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS - Operational Policy
Rules for any AI agent (Claude Code, local LLMs, MCP clients) working in this
repo or in a vault created from vault-template/.
Local maintainer instructions
- At the start of every task, check whether
AGENTS.local.mdexists in the repository root. - If it exists, read it and follow it together with this file. It is git-ignored: never commit it and never quote it in tracked files, commit messages, issues or pull requests.
- It may add restrictions. It must not relax or contradict this file. If the two conflict, follow this file and report the conflict to the maintainer.
The contract: unified reading, segregated writing
- Reading: all three vaults (work, ai, user) are indexed together. Query
the RAG server (
POST :8765/search) for grounded context instead of guessing. - Writing: routed by content type per
rag/routing.json.- Your own identity, interaction rules, and observations about the collaboration go to the ai vault.
- Durable facts about the user are staged in the user vault
_inbox/, never written directly into its curated namespaces. - Operational work goes to the work vault domain it belongs to (CloudOps, FinOps, DevOps, SecOps, Architecture, Weekly).
- When unsure, default to the work vault and tag the note
needs-routing.
Standing behavioral, git, language, and security policies live in
standards/canonical/. Read them; they govern how you act here.
Boundaries
Always
- Write vault files atomically (temp file + rename); never truncate in place.
- Keep
_Index/Active Context.mdand_Index/Open Loops.mdcurrent when work state changes; they are the session-start context for every agent. - New architecture decisions go to
Architecture/decisions/using the ADR template, numbered sequentially. - English only in all committed artifacts.
Ask first
- Changing the vault folder structure or index schema.
- Adding dependencies.
Never
- Hardcode personal paths; every path comes from config or env.
- Commit secrets, tokens, or anything matching the anonymization gate
(
scripts/anonymization-check.shruns on pre-commit and pre-push). - Rewrite
rag/build_index.pychunking logic without regenerating the index.
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.
- 7d ago Changed · +6 lines · +100 tokens per session 88e16981b8e2
- 1mo ago Changed · +7 lines · +70 tokens per session ecc81de4b793
- 1mo ago Changed · +2 lines · +62 tokens per session fa4c5153843c
- 1mo ago First seen · 57 lines · 655 tokens per session scan A 4fefbe358d33
engineering-os AGENTS.md is an instructions file published in the GitHub repository tanya-ok/engineering-os (2 stars, last pushed 7d ago), licensed MIT. It adds 887 tokens to every session, about $0.0035 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 2026-08-31.
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).
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