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/soenkenils/mailbox-mcp-server/copilot-instructionsgit clone --depth 1 https://github.com/soenkenils/mailbox-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/soenkenils/mailbox-mcp-server/copilot-instructions)<a href="https://agentmods.dev/instructions/soenkenils/mailbox-mcp-server/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/soenkenils/mailbox-mcp-server/copilot-instructions.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 | $0.00150 | $0.00150 |
| Opus 5 | $0.00075 | $0.00075 |
| Sonnet 5 | $0.00030 | $0.00030 |
| Haiku 4.5 | $0.00015 | $0.00015 |
Grade A, and why
mailbox-mcp-server copilot-instructions.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.
What it actually says
Copilot Instructions
Style
- ES modules, destructured imports, double quotes, 2 spaces, semicolons
- Arrow functions, async/await, object/array destructuring
Commands
bun dev- development serverbun run test- run tests (using vitest)bun run test:watch- run tests in watch modebun run test:coverage- run tests with coveragebun run check- lint and formatbun run test:imap- IMAP integration test
Workflow
- Try to use a TDD approach first
- Run tests and formatting after code changes
- Use single tests for performance
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 First seen · 22 lines · 150 tokens per session scan A f2e2f1272e44
mailbox-mcp-server copilot-instructions.md is an instructions file published in the GitHub repository soenkenils/mailbox-mcp-server (4 stars, last pushed 2mo ago), licensed MIT. It adds 150 tokens to every session, about $0.0007 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 2026-08-31.
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