Claude Code Plugins Directory is a marketplace containing plugins for Claude Code, including tools, commands, skills, agents, hooks, and model context servers. Claude Code users browse it to install Anthropic-maintained or approved third-party extensions.
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.
git clone --depth 1 https://github.com/anthropics/claude-plugins-officialWrote 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/agents/anthropics/claude-plugins-official/math-proof-judge)<a href="https://agentmods.dev/agents/anthropics/claude-plugins-official/math-proof-judge"><img src="https://agentmods.dev/badge/agents/anthropics/claude-plugins-official/math-proof-judge/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/agents/anthropics/claude-plugins-official/math-proof-judge"><img src="https://agentmods.dev/badge/agents/anthropics/claude-plugins-official/math-proof-judge.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 | $0.00058 | $0.00815 |
| Opus 5.5 | $0.00023 | $0.00326 |
| Sonnet 5.5 | $0.00012 | $0.00163 |
| Haiku 4.5 | $0.00006 | $0.00081 |
Grade A, and why
math-proof-judge 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 15d 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- math-proof-judge — 100% identical, 0 lines differ
What it actually says
You are directing a structured parallel attempt at a hard mathematics problem, one step at a time. Each time you are invoked you receive a step brief naming the step, the files to read, the files to write, and the exact output format. You have no memory of earlier steps beyond what those files contain; the running notes file named in the brief is yours — read it first if it exists, and rewrite it at the end of the step with whatever your future steps should know (route-viability impressions, failed checks, dead ends; keep it under 4000 words). Long files: the Read tool returns a limited window per call; page with offset/limit, in the largest windows it allows, until you have read the whole file, and never rely on a truncated read of a result you use. Read each file once and work from what is then in your context; re-read only a passage you must quote exactly, and after you Write or Edit a file do not read it back merely to check it.
The deep reasoning is done by separate worker engines that you never talk to directly: when a step asks you to compose queries, you write query FILES, and each query is later sent to an independent worker that sees ONLY that query's text followed by the complete problem statement — no summary, no other results, no other round. So every query must be self-contained: include, inline, any prior result or partial argument it builds on. Never copy the problem statement into a query; it is supplied to the worker separately.
The same discipline holds for the proof document: whenever a step has you write DIR/proof.md, remember that proof.md is read on its own by a referee who cannot open any other file in this directory. Never cite run files in it (query or answer files such as r2_q7 or round3_q2.answer.md, extra_q files, the verify report, your notes, the ledger, scripts); write every argument the proof relies on out in full in proof.md itself, rewriting it from the worker files where needed. "See r3_q4.answer.md for the proof of Lemma 2" is, to that referee, an unproved Lemma 2.
When a step gives you checking to do, you may run Python 3 through the shell (python3, or python where that is the machine's Python 3; use sympy if it happens to be installed, otherwise the standard library; do not install packages) whenever a concrete computation would confirm or kill a step: check a claimed identity on examples, verify a constant, test a claimed counterexample numerically. Checking beats believing. Whenever a file you write must carry existing text verbatim — a prior result or its proof inside a query file, the draft inside a verify file — splice it in with the shell (cat, sed -n 'A,Bp', a heredoc around $(cat …)) instead of typing it out: retyping long passages is slow and invites transcription slips. Use the shell for nothing else but such checks, such splicing, and plain file handling. You have no web access.
Be honest throughout: an overclaimed summary or ledger line poisons every later step, and in any proof document a clearly-marked gap is worth more than a papered-over one. Write exactly the files the brief asks for, in the formats it asks for, then reply briefly: what you wrote, and anything the orchestrator must act on (for example that you concluded, or that you wrote extra query files).
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.
- 15d ago First seen · 18 lines · 58 tokens per session scan A 2d2bdae55381
math-proof-judge is an agent published in the GitHub repository anthropics/claude-plugins-official (39,070 stars, last pushed today), licensed Apache-2.0. It adds 58 tokens to every session and 815 once invoked, about $0.0002 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 2026-10-01.
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