What is Crux AGENTS.md?

Repository instructions for Crux, a local-first search and memory engine whose stored records can be checked for tampering.

Understanding Crux’s architecture and trust rules, then verifying claims and testing related code.

They point agents to the project’s code map, documented claims, guarantees, threat model, and specifications before making changes.

How CueCrux/Crux configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to CueCrux/Crux. 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/CueCrux/Crux/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/CueCrux/Crux

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/cuecrux/crux/agents-md/github.svg)](https://agentmods.dev/instructions/cuecrux/crux/agents-md)

Your own site

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

Per session 1,451 This file is loaded in full into every session.

When invoked 1,451 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	$0.01451	$0.01451
Opus 5.5	$0.00580	$0.00580
Sonnet 5.5	$0.00290	$0.00290
Haiku 4.5	$0.00145	$0.00145

Measured 1mo ago against content hash 47abf7383545, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

Crux 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 · 95 lines

How it starts

The opening of the file, as written. The whole thing — 95 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Crux is a local-first retrieval and memory engine whose storage and receipts are cryptographically tamper-evident. Every receipt-bearing operation produces a signed, replayable CROWN receipt; sealed segments (.ccxseg) are BLAKE3 hash-chained and independently verifiable offline.

This file is an index, not the content. The detail lives in docs/agent/. Start here, then follow the reading order. Everything is anchored by symbol name (greppable) and CI-verified, so you can trust the references — but verify the claims yourself (below).

Reading order (start here)

docs/agent/CODEMAP.md — what each of the 28 crates owns + key symbols.
docs/agent/CLAIMS.md — each product claim mapped to the code and the test that proves it.
docs/agent/INVARIANTS.md — the cryptographic + data guarantees (I1–I6) and where they hold.
docs/THREAT_MODEL.md — trust boundaries and stated limitations.
docs/spec/receipt-v1.md — the on-the-wire receipt format.

Machine-readable index (parse this, no NL needed): docs/agent/repo-manifest.yaml. Link map: /llms.txt. Vocabulary (CROWN, CCXI, CRC-v1, cruxpack, lane, passport): docs/agent/GLOSSARY.md.

Live code map (dogfood). A running daemon can serve this repo's AST-derived structure back to you: register the checkout (POST /v1/repos with root_path), then GET /v1/repos/{id}/codemap?tenant_id=…&format=summary|full — same scanner as /console/codegraph. The curated CODEMAP.md is the reading order; the endpoint is ground truth. Per-crate context lives in crates/<name>/AGENTS.md (nearest file wins).

Building against the daemon instead of modifying it? Different docs: connect via MCP and read docs/agent-guide.md (budgets, sessions, handoffs) and docs/mcp-system-prompt.md (the full tool surface); HTTP/SDK integration starts at docs/developer-portal.md.

Verify the claims yourself (do not trust this file)

cargo test --workspace
corecruxctl verify-store --strict — per-segment BLAKE3 re-derivation + chain walk
corecruxctl replay --strict — recompute + compare
receipt conformance vectors: crates/corecrux-receipts/vectors/
fuzz targets (nightly): fuzz/fuzz_targets/ — cargo fuzz run segment_decode

Read the full file on GitHub · 95 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 Changed 47abf7383545
2mo ago First seen · 95 lines · 1,451 tokens per session scan A 02e5612c5e01

Subscribe to this mod's changes

Crux AGENTS.md is an instructions file published in the GitHub repository CueCrux/Crux (2 stars, last pushed 12d ago), licensed Apache-2.0. It adds 1,451 tokens to every session, about $0.0058 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.

LLM Memory and context Security agent-memory ai-agents claude fact-store local-first

Crux AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
Crux AGENTS.mdCueCrux/Crux	Instructions file	2	12d ago	Apache-2.0	A	1,451	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	yesterday	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

Crux: Instructions file for Codex