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 skills/mathematic-inc/earl/secure-agentnpx skills add mathematic-inc/earl --skill secure-agentgit clone --depth 1 https://github.com/mathematic-inc/earlWhat 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 | $0.00048 | $0.01851 |
| Opus 5 | $0.00024 | $0.00925 |
| Sonnet 5 | $0.00010 | $0.00370 |
| Haiku 4.5 | $0.00005 | $0.00185 |
Grade A, and why
secure-agent scanned grade A with 1 finding 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
1. **`deniedTools`**: Blocks specific bash commands (curl, gh, stripe-cli, etc.) at the How it starts
The opening of the file, as written. The whole thing — 196 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Secure Agent
After Earl is set up and working, this skill restricts the agent's ability to bypass Earl and make raw API/CLI calls directly. Without this step, CLAUDE.md is just a suggestion.
What This Does
deniedTools: Blocks specific bash commands (curl, gh, stripe-cli, etc.) at the platform level for Claude Code. Agents cannot run these commands at all.- Egress rules: Restricts which URLs Earl templates can contact, preventing Earl itself from being used as an open proxy.
Important Limitation
deniedTools pattern matching can be bypassed via alternative tools (python3 -c "import urllib...", node -e "fetch(...)", etc.). This blocks accidental or habitual CLI use — the
common case. For stronger containment, pair with OS-level firewall rules or a network proxy.
Platform Support
| Platform | Mechanism | Hard restriction? |
|---|---|---|
| Claude Code | deniedTools in .claude/settings.json |
Yes — platform enforced |
| Cursor | .cursor/mcp.json or Cursor settings UI |
Partial — check Cursor docs for per-tool restrictions |
| Windsurf | .windsurf/mcp.json or Windsurf settings UI |
Partial — check Windsurf docs for per-tool restrictions |
| Claude Desktop | No bash access | N/A |
| Non-MCP CLI agents | CLAUDE.md instructions only | No — advisory only |
This skill primarily targets Claude Code. Instructions for other platforms are best-effort.
Step 1: Check Coverage
Only deny tools for services that have Earl templates. Denying a tool for a service with no Earl template would leave the agent unable to interact with that service at all.
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 · 196 lines · 48 tokens per session scan A ee9871116fb0
secure-agent is a skill published in the GitHub repository mathematic-inc/earl (113 stars, last pushed 5d ago), licensed Apache-2.0. It adds 48 tokens to every session and 1,851 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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