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/foundry-works/foundry-mcp/claude-mdgit clone --depth 1 https://github.com/foundry-works/foundry-mcpWrote 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/foundry-works/foundry-mcp/claude-md)<a href="https://agentmods.dev/instructions/foundry-works/foundry-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/foundry-works/foundry-mcp/claude-md.svg" alt="Measured on agentmods" 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 | $0.02118 | $0.02118 |
| Opus 5 | $0.01059 | $0.01059 |
| Sonnet 5 | $0.00424 | $0.00424 |
| Haiku 4.5 | $0.00212 | $0.00212 |
Grade A, and why
foundry-mcp 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 5d 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.
This is a copy
95% identical to foundry-mcp AGENTS.md — 68 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 44 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE Agent Triage Playbook
You are operating inside the foundry-mcp repository, which adheres to the MCP Tool Industry Best Practices under dev_docs/mcp_best_practices. Use this playbook at the start of every session and whenever scope changes.
1. Session Auto-Triage
- Kickoff scan – Skim dev_docs/mcp_best_practices/README.md#L24-L77 to refresh the document index and review checklist.
- Scope-to-doc mapping – For each planned change, map the work to the decision matrix below and re-open the referenced docs before editing:
- Contracts / new tools / helper updates → Re-read dev_docs/codebase_standards/mcp_response_schema.md (canonical response contract), dev_docs/mcp_best_practices/01-versioned-contracts.md#L9-L127, dev_docs/mcp_best_practices/02-envelopes-metadata.md#L30-L285, dev_docs/mcp_best_practices/03-serialization-helpers.md#L29-L220, dev_docs/mcp_best_practices/04-validation-input-hygiene.md#L10-L223, and dev_docs/mcp_best_practices/08-security-trust-boundaries.md#L10-L345.
- Pagination / batching / error semantics → Re-read dev_docs/mcp_best_practices/06-pagination-streaming.md#L32-L332 and dev_docs/mcp_best_practices/07-error-semantics.md#L11-L274.
- Observability / resiliency / timeout work → Re-read dev_docs/mcp_best_practices/05-observability-telemetry.md#L12-L333 and dev_docs/mcp_best_practices/12-timeout-resilience.md#L12-L398.
- Concurrency / async orchestration / parallelism → Re-read dev_docs/mcp_best_practices/15-concurrency-patterns.md#L10-L420 (and dev_docs/mcp_best_practices/12-timeout-resilience.md for cancellation strategy).
- LLM ergonomics / tool metadata → Re-read dev_docs/mcp_best_practices/11-ai-llm-integration.md#L11-L352 and dev_docs/mcp_best_practices/13-tool-discovery.md#L12-L505, and consult dev_docs/codebase_standards/naming-conventions.md to keep tool prefixes canonical.
- Ambiguity rule – When uncertainty exists, re-read the full relevant section(s) instead of relying on summaries.
- Log references – Note the consulted sections in your task plan or worklog so reviewers know which guidance informed the change.
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.
- 5d ago First seen · 44 lines · 2,118 tokens per session scan A 9f68484766d2
foundry-mcp CLAUDE.md is an instructions file published in the GitHub repository foundry-works/foundry-mcp (4 stars, last pushed 5mo ago), licensed MIT. It adds 2,118 tokens to every session, about $0.0106 per session on Opus 5. A static security scan graded it A with 0 findings. It is 95% identical to foundry-mcp AGENTS.md, differing in 68 lines, and is treated as a copy.
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