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/gwhthompson/grist-mcp-server/javascript-testing-patternsnpx skills add gwhthompson/grist-mcp-server --skill javascript-testing-patternsgit clone --depth 1 https://github.com/gwhthompson/grist-mcp-serverWhat 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 | $0.00063 | $0.06351 |
| Opus 5 | $0.00032 | $0.03175 |
| Sonnet 5 | $0.00013 | $0.01270 |
| Haiku 4.5 | $0.00006 | $0.00635 |
Grade B, and why
javascript-testing-patterns scanned grade B 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.
Sends data to an external URLmediumData exfiltration
A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.
const response = await fetch('https://api.example.com/users', { method: 'POST', The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
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 · 1,026 lines · 63 tokens per session scan B 91bd0860da65
javascript-testing-patterns is a skill published in the GitHub repository gwhthompson/grist-mcp-server (3 stars, last pushed 7mo ago), with no licence file. It adds 63 tokens to every session and 6,351 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it B with 1 finding (sends data to an external url). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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