ContextEngine: Instructions file for Claude Code

CLAUDE.md

ContextEngine CLAUDE.md is an instructions file for Claude Code from FASTPROD/ContextEngine. It costs 3,079 tokens per session, scanned B, original, no licence file.

A project instruction file for Claude Code that explains how to work on FASTPROD/ContextEngine, including its architecture, context handling, and rules for using multiple agents.

In plain words
What is it for?
Use it when asking Claude Code to modify, review, or plan work in the FASTPROD/ContextEngine repository.
Why use it?
It gives the coding agent the project rules before work begins, helping prevent incorrect changes and unnecessary multi-agent costs.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md.

This is FASTPROD/ContextEngine's own configuration. It tells Claude Code how to work on ContextEngine itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything ContextEngine configures →

Reuse

Borrowing it

Nothing to install: this file belongs to FASTPROD/ContextEngine. 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/FASTPROD/ContextEngine/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/FASTPROD/ContextEngine

Made for: Claude Code.

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.

agentmods badge for ContextEngine CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/fastprod/contextengine/claude-md/github.svg)](https://agentmods.dev/instructions/fastprod/contextengine/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/fastprod/contextengine/claude-md"><img src="https://agentmods.dev/badge/instructions/fastprod/contextengine/claude-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.

agentmods 80×15 button for ContextEngine CLAUDE.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/fastprod/contextengine/claude-md"><img src="https://agentmods.dev/badge/instructions/fastprod/contextengine/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 3,079 This file is loaded in full into every session.
When invoked 3,079 The same file — it is already loaded in full.
Security scan B 2 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.03079 $0.03079
Opus 5.5 $0.01232 $0.01232
Sonnet 5.5 $0.00616 $0.00616
Haiku 4.5 $0.00308 $0.00308

Measured 2mo ago against content hash 4f44ab0e98c9, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade B, and why

ContextEngine CLAUDE.md scanned grade B with 2 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 2mo 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.

Reads agent configuration directoriesmediumAgent snooping

.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.

(1) `mcpServers` in `~/.claude/settings.json` is not read by Claude Code at all; MCP servers live in

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

4. **All `exec()` calls must use hardcoded strings** — `agents.ts` and `collectors.ts` use `execSync` for git/docker/pm2 data collection. Never interpolate user input into shell commands.
CLAUDE.md · 139 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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.

  1. 2mo ago Changed · +11 lines · +377 tokens per session 4f44ab0e98c9
  2. 2mo ago First seen · 128 lines · 2,702 tokens per session scan B 33f5fbfab293

Subscribe to this mod's changes

ContextEngine CLAUDE.md is an instructions file published in the GitHub repository FASTPROD/ContextEngine (3 stars, last pushed 1mo ago), with no licence file. It adds 3,079 tokens to every session, about $0.0123 per session on Opus 5.5. A static security scan graded it B with 2 findings (reads agent configuration directories, runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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