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/jahands/prompts/mermaidgit clone --depth 1 https://github.com/jahands/promptsWrote 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/rules/jahands/prompts/mermaid)<a href="https://agentmods.dev/rules/jahands/prompts/mermaid"><img src="https://agentmods.dev/badge/rules/jahands/prompts/mermaid.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 5.1 | $0.00023 | $0.00735 |
| Opus 5 | $0.00012 | $0.00367 |
| Sonnet 5 | $0.00005 | $0.00147 |
| Haiku 4.5 | $0.00002 | $0.00073 |
Grade A, and why
mermaid 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.
What it actually says
subgraph ProcessingLayer ["📊 Processing Layer"]
Client["<p>typed client<br/>interface</p>"]
Methods["<p>Method calls:<br/>client.getData({id: string})<br/>client.process({data: object})</p>"]
end
classDef userNode fill:#4a90e2,stroke:#357abd,color:#ffffff
classDef dbNode fill:#50c878,stroke:#3da35d,color:#ffffff
class User userNode
class DB dbNode
</example>
</mermaid-diagram-formatting>
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 · 55 lines · 23 tokens per session scan A 34de811d08a7
mermaid is a cursor rule published in the GitHub repository jahands/prompts (19 stars, last pushed 7mo ago), licensed MIT. It adds 23 tokens to every session and 735 once invoked, about $0.0001 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 2026-08-30.
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