Plannotator is a local browser-based review tool for coding agents that lets people annotate plans, documents, HTML artifacts, code diffs, and pull requests, then send feedback back to the agent. It is used by developers and teams reviewing work from agents across supported coding tools and version-control systems.
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 backnotprop/plannotator --skill plannotator-visual-explainergit clone --depth 1 https://github.com/backnotprop/plannotatorWrote 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/backnotprop/plannotator/plannotator-visual-explainer)<a href="https://agentmods.dev/skills/backnotprop/plannotator/plannotator-visual-explainer"><img src="https://agentmods.dev/badge/skills/backnotprop/plannotator/plannotator-visual-explainer/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/backnotprop/plannotator/plannotator-visual-explainer"><img src="https://agentmods.dev/badge/skills/backnotprop/plannotator/plannotator-visual-explainer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket warn
- Snyk warn
- NVIDIA SkillSpector warn
SkillSpector: 2 findings, 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 Agent Snooping · line 102 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
- medium MCP Rug Pull · line 103 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 | $0.00078 | $0.01565 |
| Opus 5.5 | $0.00031 | $0.00626 |
| Sonnet 5.5 | $0.00016 | $0.00313 |
| Haiku 4.5 | $0.00008 | $0.00156 |
Grade A, and why
plannotator-visual-explainer 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 28d 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- plannotator-visual-explainer — 94% identical, 15 lines differ
How it starts
The opening of the file, as written. The whole thing — 121 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Plannotator Visual Explainer
Three paths depending on content type. Each has its own references and structure.
Route by content type
Implementation plan, design doc, or proposal → Follow the Plan path. Read references/design-system.md and references/svg-patterns.md. Prescriptive structure.
PR explainer, diff review, or code change walkthrough → Follow the PR path. Read references/design-system.md and references/pr-components.md. Prescriptive structure.
Everything else (architecture diagrams, data tables, slide decks, project recaps, general visual explanations) → Follow the Visual explainer path. Delegates to nicobailon/visual-explainer with Plannotator theme tokens.
Delivery
Always deliver via Plannotator's annotation UI. Do NOT use open or xdg-open.
For any deliverable that uses Mermaid, render every diagram with Mermaid 12 in both the light
and dark palettes before opening the annotation UI. Rendering is a hard gate: an exception,
empty SVG, or error output such as aria-roledescription="error" or Syntax error in text
means the explainer is not deliverable. Fix the diagram or theme configuration and rerun both
palettes until every SVG passes.
For zoomable diagram shells, additionally zoom to the maximum and pan to all extremes in both palettes before delivering: the figure caption must stay fully legible throughout (see references/diagram-shell.md).
Plans/proposals (user should approve/deny):
plannotator annotate <file> --gate
Everything else (informational):
plannotator annotate <file>
Plan path
For implementation plans, design docs, feature specs, migration guides, and proposals.
Before generating, read:
references/design-system.md— Plannotator theme tokens, typography, component patternsreferences/svg-patterns.md— inline SVG building blocks for architecture diagrams, flowcharts, data flow
Document structure (in order, pick what fits):
What ships with it
6 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.
- 28d ago Changed · +3 lines 147c28e043a9
- 1mo ago First seen · 118 lines · 78 tokens per session scan A 915b90901bce
plannotator-visual-explainer is a skill published in the GitHub repository backnotprop/plannotator (9,452 stars, last pushed today), licensed Apache-2.0. It adds 78 tokens to every session and 1,565 once invoked, about $0.0003 per session on Opus 5.5. 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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