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 rules/localrivet/gomcp/good-behaviourgit clone --depth 1 https://github.com/localrivet/gomcpWhat 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 | $0.00120 | $0.00120 |
| Opus 5 | $0.00060 | $0.00060 |
| Sonnet 5 | $0.00024 | $0.00024 |
| Haiku 4.5 | $0.00012 | $0.00012 |
Grade A, and why
good-behaviour 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 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.
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
100% identical to good-behaviour — 2 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.
What it actually says
Do not hard code data into code unless specifically requested by me.
If you have an idea on why something is failing, always validate that idea with testing before changing code.
Do not write stub or fake methods. Write production ready code first time.
Do not cheat on tests and checks by adding hard-coded values or assertions.
Do not make statements about functionality working unless you have tested it. Perform your own tests first, do not assume that your changes or my changes just work until you have seen evidence from tests.
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 · 15 lines · 120 tokens per session scan A f8e45001cdd7
good-behaviour is a cursor rule published in the GitHub repository localrivet/gomcp (51 stars, last pushed 1y ago), licensed MIT. It adds 120 tokens to every session, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to good-behaviour, differing in 2 lines, and is treated as a copy.
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