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 ussumant/useful-agent-skills --skill explainer-diagramsgit clone --depth 1 https://github.com/ussumant/useful-agent-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/ussumant/useful-agent-skills/explainer-diagrams)<a href="https://agentmods.dev/skills/ussumant/useful-agent-skills/explainer-diagrams"><img src="https://agentmods.dev/badge/skills/ussumant/useful-agent-skills/explainer-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/ussumant/useful-agent-skills/explainer-diagrams"><img src="https://agentmods.dev/badge/skills/ussumant/useful-agent-skills/explainer-diagrams.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00122 | $0.02235 |
| Opus 5 | $0.00061 | $0.01118 |
| Sonnet 5 | $0.00024 | $0.00447 |
| Haiku 4.5 | $0.00012 | $0.00224 |
Grade A, and why
explainer-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 today.
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 — 140 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Explainer diagrams
A diagram in this grammar is a scene: shapes, positions, and arrows that
carry the meaning, with few words. The first attempt at this usually comes
out as a table in nice colors. The verdict that produced this skill was
"they're not visual, they look boring." Read examples/severance-week/
before your first diagram: index.html is the source of seven diagrams and
out/ holds the PNGs they produced. That is the reference implementation.
The grammar
| token | value | used for |
|---|---|---|
blue #1a52e0 |
flow, structure, the real thing | card strokes, solid arrows, solid nodes, stat numbers, index badge |
orange #d66b2f |
intervention, return path, the outside hand | dashed arrows, seed cards (#fff3ea tint), rewind |
panel #f5f7ff |
containers, callouts | dashed container fill, callout background |
gray #aaa / #f2f2f2 |
invalid, scripted, never happened | hollow nodes, struck-through lines, "never entered" boxes |
text #666, muted #767676, ink #000 |
Type: Pixelify Sans (Google Fonts) for the title and the callout heading
only; system mono for everything else; system sans bold only for card labels
and node names. Cards are white, 1px stroke, border-radius: 3px. Arrows use
a 6×6 triangle <marker>, one per diagram with a unique id.
Components (all in template.html): .shot (1100px white sheet, 40px
padding; the PNG is this element) → .shot-head (blue mono index 01,
Pixelify <h2>, one-line mono <p>) → .scene (1020px, #fbfbfb, 1px
border; the picture) → optional .stat-row of .stat-tile (big blue mono
number over a gray label) → optional .callout (blue left border, Pixelify
one-liner + one mono sentence) → optional .footnote (11px mono caveat).
Card variants: .tint-orange, .tint-blue, .solid, .dashed, .gray;
inside a card: .tag (mono caps), .label (sans bold), .sub (mono body).
components.md has copy-paste snippets for every piece.
Scene, not table
- One idea per diagram. The title says it, the scene shows it, the callout says what it means in one line. If it needs a paragraph, it is two diagrams.
- Shapes carry the meaning: a line that thickens day by day, a path that
stops short of a box with an
×, a hollow node beside solid ones, a strike-through on the canned line, a bar split into scored segments. The reader should get it before reading a word. - Words are receipts, not prose: quotes ≤ 14 words with an ellipsis, never reworded; ids and times in mono beside them; ≤ ~10 text objects per scene.
- Nothing smaller than 13px at the 1020px scene. Most newsletter and forum layouts show the PNG at ~700px wide. Stat numbers 24px, titles 27px.
- Every number and quote comes from a source file, verbatim. A caption or a callout is a factual claim; check it against the source before shooting.
- Footnotes carry method caveats. Never reference an unpublished URL or "see 01–06 above" inside a PNG that will travel on its own.
What ships with it
15 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.
- components.md 7.7 KB
- examples/before.png 334 KB
- examples/severance-week/index.html 42 KB
- examples/severance-week/out/03-before-after-architecture.png 106 KB
- examples/severance-week/out/13-one-paragraph-five-days.png 160 KB
- examples/severance-week/out/19-same-whisper-two-minds.png 160 KB
- examples/severance-week/out/20-how-one-line-got-made.png 217 KB
- examples/severance-week/out/22-two-fridays.png 118 KB
- examples/severance-week/out/24-by-the-numbers.png 88 KB
- examples/severance-week/out/25-what-didnt-work.png 185 KB
- examples/severance-week/plan.json 3.6 KB
- plan.example.json 1.1 KB
- README.md 4.3 KB
- shoot.mjs 10.0 KB runs code
- template.html 10 KB
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.
- today First seen · 140 lines · 122 tokens per session scan A 326b9224645b
explainer-diagrams is a skill published in the GitHub repository ussumant/useful-agent-skills (5 stars, last pushed today), licensed MIT. It adds 122 tokens to every session and 2,235 once invoked, about $0.0006 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 2026-09-14.
Other skills, from other repositories
web-quality-audit
Run an evidence-led web quality audit covering performance, accessibility, SEO, best practices, and agentic browsing. Use when asked to "audit my site", "review web quality", "run lighthouse audit", "check page quality", or "optimize my website".
agent-ready-scan-site
Sub-skill: Scan any URL for agent readiness. Checks 18 standards across 5 categories, returns readiness level (0-5), status of all checks, and fix instructions.
agent-ready-webmcp
Sub-skill de agent-ready-cloudflare: Implement WebMCP.
web-data-extraction
Use when extracting data from web pages. Covers choosing between an API, static parsing, and a browser, handling JavaScript-rendered content, resilient selectors, rate limiting, and scraping responsibly.
e2e-playwright
Use when writing end-to-end browser tests with Playwright. Covers resilient locators, auto-waiting, network interception, authentication reuse, parallelization, and eliminating flakiness.
web-app-testing
Use when testing a web application interactively — verifying a feature, reproducing a bug, or checking a flow in a real browser. Covers systematic exploration, console and network inspection, and reporting what you find.