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 product-on-purpose/pm-skills --skill utility-mermaid-diagramsgit clone --depth 1 https://github.com/product-on-purpose/pm-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/product-on-purpose/pm-skills/utility-mermaid-diagrams)<a href="https://agentmods.dev/skills/product-on-purpose/pm-skills/utility-mermaid-diagrams"><img src="https://agentmods.dev/badge/skills/product-on-purpose/pm-skills/utility-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/product-on-purpose/pm-skills/utility-mermaid-diagrams"><img src="https://agentmods.dev/badge/skills/product-on-purpose/pm-skills/utility-mermaid-diagrams.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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 | $0.00061 | $0.01441 |
| Opus 5 | $0.00030 | $0.00720 |
| Sonnet 5 | $0.00012 | $0.00288 |
| Haiku 4.5 | $0.00006 | $0.00144 |
Grade A, and why
utility-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 9d 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 — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mermaid Diagrams
Create effective, syntactically valid mermaid diagrams for product documents.
When to Use
- Creating mermaid diagrams for PRDs, specs, roadmaps, or stakeholder presentations
- Choosing which of 15 diagram types fits a specific communication need
- Debugging mermaid code that won't render or renders incorrectly
- Reviewing diagrams for clarity, accuracy, and accessibility
When NOT to Use
- Exporting diagrams to image files (PNG/SVG) - that's a rendering tool concern
- Using non-mermaid diagramming tools (Figma, Lucidchart, draw.io)
- Creating purely decorative visuals with no informational purpose
- Producing a full customer-journey artifact (stages, touchpoints, emotional curve, pain points) rather than a standalone diagram - use
discover-journey-map, which composes this skill for its timeline or flowchart section
The Cardinal Rule
Don't diagram what a list can say.
Diagrams earn their place when they reveal relationships, branching, or flow that prose flattens. Before creating any diagram, ask:
Does this show branching, relationships, or flow that a list or table would flatten?
- Yes → proceed with a diagram
- No → use a numbered list, bullet list, or table instead
A 5-step linear process is a list. A 5-step process with two decision points and a retry loop is a diagram.
Diagram Selection Guide
| I need to show... | Use | Also consider |
|---|---|---|
| A decision or approval process | Flowchart | State |
| Multi-service or multi-party interactions | Sequence | Flowchart |
| Feature lifecycle or status transitions | State | Flowchart |
| Work stages or pipeline status | Kanban | State |
| Release or sprint timeline with dependencies | Gantt | Timeline |
| Version history or chronological milestones | Timeline | Gantt |
| 2D prioritization (effort/impact, risk/value) | Quadrant | - |
| Allocation breakdown or composition | Pie | Treemap |
| Problem decomposition or brainstorming | Mindmap | - |
| Domain models or data relationships | ER | Class |
| API or object contracts | Class | ER |
| System topology or infrastructure | Architecture | Flowchart |
| Flow quantities or budget allocation | Sankey | Pie |
| Hierarchical proportional data | Treemap | Pie |
| Trends or time-series metrics | XY-Chart | - |
What ships with it
7 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.
- 9d ago First seen · 122 lines · 61 tokens per session scan A aeb8d8462f02
utility-mermaid-diagrams is a skill published in the GitHub repository product-on-purpose/pm-skills (663 stars, last pushed yesterday), licensed Apache-2.0. It adds 61 tokens to every session and 1,441 once invoked, about $0.0003 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 2026-09-03.
Other skills, from other repositories
idea-validator
Use when the user asks to validate a product idea, stress-test an idea, evaluate whether an idea is good, or decide whether to build something. Do NOT use for prioritizing an existing backlog or reviewing a shipped feature — those need RICE scoring or a design review instead.
product-designer
Use when the user asks to review a design, critique a UI or mockup, give design feedback, or check a screen for usability and accessibility issues. Do NOT use for visual brand or aesthetic preference debates, or for reviewing copy before layout is settled.
prompt-engineer
Use when the user asks to improve, optimize, rewrite, debug, or shorten a prompt, or asks why a prompt is producing bad output. Do NOT use for writing a Claude Code SKILL.md — that needs skill structure rules, not prompt techniques.
status-update-writer
Use when the user asks to write a status update, weekly or monthly update, stakeholder update, project update, standup, status report, or QBR. Do NOT use for writing a PRD or a retro doc — those need different structures.
linkedin-post-writer
Use when the user asks to write, draft, or rewrite a LinkedIn post, turn notes or an article into a LinkedIn post, or fix a hook that is not landing. Do NOT use for X/Twitter threads, newsletters, or blog posts — those need different length and hook rules.
spec-from-conversation
Turn an unstructured stakeholder conversation, Slack thread, or meeting transcript into a structured spec (problem, goals, non-goals, success metrics, open questions). Use whenever a PM has raw conversational input and needs a first-draft spec, or when someone says "can you turn this into a doc" after a discussion.…