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/perseus-computing-llc/perseus-vault-codex/agents-mdgit clone --depth 1 https://github.com/Perseus-Computing-LLC/perseus-vault-codexWrote 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/perseus-computing-llc/perseus-vault-codex/agents-md)<a href="https://agentmods.dev/instructions/perseus-computing-llc/perseus-vault-codex/agents-md"><img src="https://agentmods.dev/badge/instructions/perseus-computing-llc/perseus-vault-codex/agents-md.svg" alt="Measured on agentmods" 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 | $0.00496 | $0.00496 |
| Opus 5 | $0.00248 | $0.00248 |
| Sonnet 5 | $0.00099 | $0.00099 |
| Haiku 4.5 | $0.00050 | $0.00050 |
Grade A, and why
perseus-vault-codex 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.
What it actually says
AGENTS.md — guidance for Codex working in this repo
This file is read by Codex to understand the project. It also documents how the memory tools this package provides should be used by an agent.
What this project is
perseus-vault-codex is an MCP stdio server that gives a Codex agent persistent,
encrypted, local-first memory by wrapping the Perseus Vault
binary. It exposes five tools: perseus_remember, perseus_recall,
perseus_forget, perseus_reflect, perseus_status.
Using the memory tools (for any Codex agent with this server installed)
- At the start of a task, call
perseus_recallwith a short description of what you're about to do. Pull in past decisions, conventions, and gotchas. - When you learn something durable — a build command, a code-style rule, an
architectural decision, a non-obvious gotcha, a user preference — call
perseus_remember. Use a stablekeyso re-learning updates rather than duplicates. - When a memory is wrong or stale,
perseus_forgetit by key. - To synthesize across many memories, use
perseus_reflect. - Memories persist across sessions and are encrypted at rest. Do not store secrets you wouldn't want in a local encrypted DB.
Developing this package
- Python ≥ 3.9, zero runtime dependencies (the stdio transport is vendored in
src/perseus_vault_codex/_vault_client.py). - Run tests:
pytest -q. Unit tests use a fake vault client and need no binary. Integration tests run only whenPERSEUS_VAULT_BINpoints at a realperseus-vaultbinary (or it's on PATH). - stdout is the JSON-RPC channel — never
print()to stdout in the server path; log to stderr via the_loghelpers. - The curated tool schemas live in
tools.py::TOOL_SCHEMAS; keep the surface at five tools — that minimalism is the point.
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.
- 2d ago First seen · 37 lines · 496 tokens per session scan A 4fa9e47a272a
perseus-vault-codex AGENTS.md is an instructions file published in the GitHub repository Perseus-Computing-LLC/perseus-vault-codex (0 stars, last pushed 1mo ago), licensed MIT. It adds 496 tokens to every session, about $0.0025 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.
Other instructions, from other repositories
personal-model AGENTS.md
Instructions for Intuition-Lab/personal-model, covering agents.md, runtime boundary, commands, pipeline and documentation map.
plur CLAUDE.md
Instructions for plur-ai/plur, covering claude.md, what is plur, development, package dependency and version bumps.
personal-model CLAUDE.md
Instructions for Intuition-Lab/personal-model: Read and follow AGENTS.md. It is the single agent orientation for this repository: Runtime boundary, commands, architecture, invariants, current documentation, privacy rules, and DCO workflow.
engraphis AGENTS.md
Instructions for Coding-Dev-Tools/engraphis, covering agents.md — engraphis, 0. read this first — two architectures live in one package, 1. commands, ── unified dashboard + memory inspector ── and 2. the v2 recall pipeline (where the real work is).
paxm AGENTS.md
Instructions for pax-beehive/paxm, covering paxm 开发要求, git 与协作, 架构边界, 代码与验证 and 文档与发布.
brigade AGENTS.md
Instructions for escoffier-labs/brigade, covering agents.md, definition of done, rules, orientation and memory handoff.