Borrowing it
Nothing to install: this file belongs to Arkya-AI/claude-context-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/Arkya-AI/claude-context-os/main/CLAUDE.mdgit clone --depth 1 https://github.com/Arkya-AI/claude-context-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/arkya-ai/claude-context-os/claude-md)<a href="https://agentmods.dev/instructions/arkya-ai/claude-context-os/claude-md"><img src="https://agentmods.dev/badge/instructions/arkya-ai/claude-context-os/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.
<a href="https://agentmods.dev/instructions/arkya-ai/claude-context-os/claude-md"><img src="https://agentmods.dev/badge/instructions/arkya-ai/claude-context-os/claude-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 | $0.00687 | $0.00687 |
| Opus 5 | $0.00344 | $0.00344 |
| Sonnet 5 | $0.00137 | $0.00137 |
| Haiku 4.5 | $0.00069 | $0.00069 |
Grade A, and why
claude-context-os CLAUDE.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 9d 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 — 50 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
Session Start
Read the latest handoff in docs/summaries/ if one exists. Load only the files that handoff references — not all summaries. If no handoff exists, ask: what is the project, what type of work, what is the target deliverable.
Before starting work, state: what you understand the project state to be, what you plan to do this session, and any open questions.
Identity
You work with [Your Name], [your role and context]. Adapt your communication style and outputs to match this domain.
Rules
- Do not mix unrelated project contexts in one session.
- Write state to disk, not conversation. After completing meaningful work, write a summary to docs/summaries/ using templates from templates/claude-templates.md. Include: decisions with rationale, exact numbers, file paths, open items.
- Before compaction or session end, write to disk: every number, every decision with rationale, every open question, every file path, exact next action.
- When switching work types (research → writing → review), write a handoff to docs/summaries/handoff-[date]-[topic].md and suggest a new session.
- Do not silently resolve open questions. Mark them OPEN or ASSUMED.
- Do not bulk-read documents. Process one at a time: read, summarize to disk, release from context before reading next. For the detailed protocol, read docs/context/processing-protocol.md.
- Sub-agent returns must be structured, not free-form prose. Use output contracts from templates/claude-templates.md.
Where Things Live
- templates/claude-templates.md — summary, handoff, decision, analysis, task, output contract templates (read on demand)
- docs/summaries/ — active session state (latest handoff + project brief + decision records + source summaries)
- docs/context/ — reusable domain knowledge, loaded only when relevant to the current task
- processing-protocol.md — full document processing steps
- archive-rules.md — summary lifecycle and file archival rules
- docs/archive/ — processed raw files. Do not read unless explicitly told.
- output/deliverables/ — final outputs
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.
- 9d ago First seen · 50 lines · 687 tokens per session scan A 618ec587e3e7
claude-context-os CLAUDE.md is an instructions file published in the GitHub repository Arkya-AI/claude-context-os (295 stars, last pushed 6mo ago), licensed MIT. It adds 687 tokens to every session, about $0.0034 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 2026-08-30.
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