Borrowing it
Nothing to install: this file belongs to whats2000/isaacsim-mcp-server. 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/whats2000/isaacsim-mcp-server/main/CLAUDE.mdgit clone --depth 1 https://github.com/whats2000/isaacsim-mcp-serverWrote 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/whats2000/isaacsim-mcp-server/claude-md)<a href="https://agentmods.dev/instructions/whats2000/isaacsim-mcp-server/claude-md"><img src="https://agentmods.dev/badge/instructions/whats2000/isaacsim-mcp-server/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/whats2000/isaacsim-mcp-server/claude-md"><img src="https://agentmods.dev/badge/instructions/whats2000/isaacsim-mcp-server/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 | $0.03594 | $0.03594 |
| Opus 5 | $0.01797 | $0.01797 |
| Sonnet 5 | $0.00719 | $0.00719 |
| Haiku 4.5 | $0.00359 | $0.00359 |
Grade A, and why
isaacsim-mcp-server 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 4d 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 — 119 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Commands
uv sync # install deps (creates .venv)
uv run pre-commit install # ruff lint+format on commit
uv run pytest # unit suite only; live tests skip unless opted in
ISAAC_MCP_LIVE_TESTS=1 uv run pytest # ALSO runs tests that MUTATE a running Isaac Sim
uv run pytest tests/test_adapter_v6.py::test_get_adapter_returns_v6_when_version_6 # single test
uv run ruff check . && uv run ruff format . # what CI enforces
uv run python add_license_headers.py # prepend the MIT header to new .py files
Live testing (unit tests alone are not sufficient — CONTRIBUTING requires verifying in a running simulator, and stating the Isaac Sim version in the PR):
./scripts/run_isaac_sim.sh # Kit + extension; --newton / --physx / ISAACSIM_ENGINE
./scripts/dev_mcp_server.sh # MCP server + extension hot-reload watcher
python scripts/smoke_test.py # one socket command per surface, pass/fail per check
python scripts/smoke_test.py --port 8767 # a second instance (e.g. 5.1 alongside 6.0)
./.venv/bin/python -m mcp dev ./isaac_mcp/server.py # MCP inspector on :5173
dev_mcp_server.sh reloads handler/adapter modules inside the running Kit process, so extension edits do not need an Isaac Sim restart. MCP-server-side edits (isaac_mcp/) do need the MCP client to restart the server.
Architecture
Two processes, one JSON-over-TCP hop (localhost:8766, ISAAC_MCP_PORT to change):
MCP client → isaac_mcp/ (FastMCP, stdio) → socket → isaac.sim.mcp_extension/ (Omniverse ext) → adapter → Isaac Sim APIs
MCP side — isaac_mcp/server.py builds FastMCP, attaches the _INSTRUCTIONS block (the agent-facing contract doc: workflow, debug loop, silent-failure map), and calls register_all_tools. Each module in isaac_mcp/tools/ exposes register_tools(mcp, get_connection); every tool serializes params, calls conn.send_command("<category>.<verb>", params), and returns json.dumps(result). Tools never raise — errors come back as {"status": "error", "message": ...} JSON strings.
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.
- 4d ago Changed · +13 lines · +352 tokens per session 0029b9241d4f
- 5d ago First seen · 106 lines · 3,242 tokens per session scan A 77c01fe4bc90
isaacsim-mcp-server CLAUDE.md is an instructions file published in the GitHub repository whats2000/isaacsim-mcp-server (64 stars, last pushed 5d ago), licensed MIT. It adds 3,594 tokens to every session, about $0.0180 per session on Opus 5. A static security scan graded it A with 0 findings. It comes from a forked repository.
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