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/flexcompute/tidy3d/claude-mdgit clone --depth 1 https://github.com/flexcompute/tidy3dWhat 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 | $0.00003 | $0.00003 |
| Opus 5 | $0.00002 | $0.00002 |
| Sonnet 5 | $0.00001 | $0.00001 |
| Haiku 4.5 | $0.00000 | $0.00000 |
Grade A, and why
tidy3d 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 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.
The source is not reproduced here
Licensed LGPL-2.1
The repository is licensed LGPL-2.1, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
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 · 1 lines · 3 tokens per session scan A a54ff182c7e8
tidy3d CLAUDE.md is an instructions file published in the GitHub repository flexcompute/tidy3d (360 stars, last pushed 26d ago), licensed LGPL-2.1. It adds 3 tokens to every session, about $0.0000 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.
Other instructions, from other repositories
pydantic-ai AGENTS.md
Instructions for pydantic/pydantic-ai, covering your primary responsibility is to the project and its users, gathering context on the task, ensuring the task is ready for implementation, philosophy and requirements of all contributions.
vizro CLAUDE.md
Claude Code instructions for mckinsey/vizro, covering vizro development guide for ai agents, development setup (across all packages), only dependency: hatch, working directory and common hatch commands across all packages.
vizro copilot-instructions.md
Copilot instructions for mckinsey/vizro, covering github copilot instructions for vizro, pull requests from bots and automated tooling and everything else.
chrono AGENTS.md
AGENTS.md instructions for projectchrono/chrono, covering repository guidelines, developers vs. users, project structure & module organization, build, test, and development commands and physics manuals & demo-first workflow.
pydantic-deepagents CLAUDE.md
Instructions for vstorm-co/pydantic-deepagents, covering claude.md, development commands, core development tasks, single test commands and project architecture.
Foam-Agent AGENTS.md
Instructions for csml-rpi/Foam-Agent, covering agents.md, what is foam-agent?, build and run, environment setup and run a simulation.