Borrowing it
Nothing to install: this file belongs to tjakoen/grain. 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/tjakoen/grain/main/CLAUDE.mdgit clone --depth 1 https://github.com/tjakoen/grainWrote 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/tjakoen/grain/claude-md)<a href="https://agentmods.dev/instructions/tjakoen/grain/claude-md"><img src="https://agentmods.dev/badge/instructions/tjakoen/grain/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/tjakoen/grain/claude-md"><img src="https://agentmods.dev/badge/instructions/tjakoen/grain/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 | $0.01482 | $0.01482 |
| Opus 5.5 | $0.00593 | $0.00593 |
| Sonnet 5.5 | $0.00296 | $0.00296 |
| Haiku 4.5 | $0.00148 | $0.00148 |
Grade A, and why
grain 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 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.
How it starts
The opening of the file, as written. The whole thing — 111 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md: GRAIN monorepo
Read this first, then the docs it points to. Keep it accurate: if you change how the workspace works (a package, a command, a rule), update this file in the same change. This repo wires into Tjakoen's personal standards, published at
https://tjakoen.github.io/standards. Reference them, don't fork them.
What this is
The Bun-workspace monorepo for the GRAIN family: four published layers that build on each other, plus a workspace-only MCP server over their built output, each its own package, no build step, everything runs on Bun straight from TypeScript. An app can adopt just the design system or the whole stack.
| Package | What it is |
|---|---|
@tjakoen/grain |
The AI-interaction design system + default theme. Every surface is operable by a human or an AI through one shared vocabulary, with the AI's presence shown as a visible signal (grain = AI). |
@tjakoen/mill |
Markdown In, Living Layouts. A Markdown to GRAIN-pages CMS. |
@tjakoen/proof |
The AI plan board. Plans are markdown; the board is a live projection that never writes back. |
@tjakoen/crumb |
The guided-tour, demo-mode, and AI-review layer. Published and live on tjakoen.github.io. |
Dependency direction runs one way: a substrate (BATCH is the reference) sits below grain, mill builds on grain, proof builds on mill, crumb builds on grain and mill. grain imports nothing from the substrate except one port. Never reach across or upward; add a port instead.
Each package carries its own CLAUDE.md and PLAN.md with that layer's rules, non-negotiables,
and hard-won lessons. Working inside a layer? Read its file first. This root file is the workspace
front door.
How I work here (non-negotiables)
The full rulebook is AI-DEVELOPMENT.md plus
SESSION-LOOP.md (session mechanics, memory,
handoff, model economy). The short version:
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 · +20 lines · +236 tokens per session f2ba5aab86f2
- 2mo ago First seen · 91 lines · 1,246 tokens per session scan A a4296e850352
grain CLAUDE.md is an instructions file published in the GitHub repository tjakoen/grain (179 stars, last pushed yesterday), licensed Apache-2.0. It adds 1,482 tokens to every session, about $0.0059 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 2026-08-30.
grain CLAUDE.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| grain CLAUDE.mdtjakoen/grain | Instructions file | 179 | yesterday | Apache-2.0 | A | 1,482 | Claude Code |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | yesterday | MIT | A | 9,719 | GitHub Copilot |
| next.js AGENTS.mdvercel/next.js | Instructions file | 143k | today | 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 |