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 skills add ccheney/robust-skills --skill mermaid-diagramsgit clone --depth 1 https://github.com/ccheney/robust-skillsWrote 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/skills/ccheney/robust-skills/mermaid-diagrams)<a href="https://agentmods.dev/skills/ccheney/robust-skills/mermaid-diagrams"><img src="https://agentmods.dev/badge/skills/ccheney/robust-skills/mermaid-diagrams/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/ccheney/robust-skills/mermaid-diagrams"><img src="https://agentmods.dev/badge/skills/ccheney/robust-skills/mermaid-diagrams.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium MCP Rug Pull · line 196 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
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 | $0.00105 | $0.02402 |
| Opus 5 | $0.00053 | $0.01201 |
| Sonnet 5 | $0.00021 | $0.00480 |
| Haiku 4.5 | $0.00011 | $0.00240 |
Grade A, and why
mermaid-diagrams 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 13d 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.
How it starts
The opening of the file, as written. The whole thing — 220 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mermaid Diagrams
Generate diagrams in markdown that render in GitHub, GitLab, VS Code, Obsidian, Notion. Syntax verified against Mermaid v11.16 (2026).
Quick Start
```mermaid
flowchart LR
A[Start] --> B{Decision}
B -->|Yes| C[Action]
B -->|No| D[Finish]
```
Quick Decision Tree
What to visualize?
├─ Process, algorithm, decision flow → flowchart
├─ API calls, service interactions → sequenceDiagram
├─ Database tables, relationships → erDiagram
├─ OOP, type hierarchy, domain model → classDiagram
├─ State machine, lifecycle → stateDiagram-v2
├─ System architecture, services → flowchart + subgraphs (or C4Context / architecture-beta)
├─ Project timeline, sprints → gantt
├─ Chronological events, milestones → timeline
├─ User experience, pain points → journey
├─ Git branches → gitGraph
├─ Brainstorming, concept hierarchy → mindmap
├─ Data distribution → pie
├─ Data trends (bar/line) → xychart
├─ Flow allocation (funnel, budget) → sankey
├─ Priority matrix → quadrantChart
├─ Task board → kanban
└─ Network packet layout → packet
Default to flowchart when unsure — it handles most "draw the system/process" requests. Prefer plain flowchart + subgraphs over architecture-beta/C4 unless the user asks for those specifically, since flowcharts render everywhere.
Diagram Types
| Type | Declaration | Best For | Status |
|---|---|---|---|
| Flowchart | flowchart LR / flowchart TB |
Processes, decisions, data flow | Stable |
| Sequence | sequenceDiagram |
API flows, service calls | Stable |
| ER | erDiagram |
Database schemas | Stable |
| Class | classDiagram |
Types, domain models | Stable |
| State | stateDiagram-v2 |
State machines | Stable |
| Gantt | gantt |
Project timelines | Stable |
| Timeline | timeline |
Chronological events | Stable |
| Journey | journey |
User experience mapping | Stable |
| Mindmap | mindmap |
Brainstorming, hierarchies | Stable |
| Git | gitGraph |
Branch visualization | Stable |
| Pie | pie |
Data distribution | Stable |
| Quadrant | quadrantChart |
Priority matrices | Stable |
| XY Chart | xychart |
Bar/line data trends | Stable (was xychart-beta) |
| Packet | packet |
Network protocol layouts | Stable (was packet-beta) |
| Kanban | kanban |
Task boards | Stable |
| Block | block |
Grid-positioned layouts | Stable (was block-beta) |
| Sankey | sankey |
Flow allocation | Experimental (was sankey-beta) |
| C4 | C4Context etc. |
System architecture | Experimental |
| Architecture | architecture-beta |
Cloud/service topology | Beta |
| Treemap | treemap-beta |
Hierarchical proportions | Beta |
| Requirement | requirementDiagram |
Requirements traceability | Stable |
What ships with it
9 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 13d ago First seen · 220 lines · 105 tokens per session scan A 33d0d6db7640
mermaid-diagrams is a skill published in the GitHub repository ccheney/robust-skills (59 stars, last pushed 16d ago), licensed MIT. It adds 105 tokens to every session and 2,402 once invoked, about $0.0005 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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