Borrowing it
Nothing to install: this file belongs to tincopper/neeko. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/tincopper/neeko/main/.agents/skills/html-effectiveness/SKILL.mdgit clone --depth 1 https://github.com/tincopper/neekoWrote 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/tincopper/neeko/html-effectiveness)<a href="https://agentmods.dev/skills/tincopper/neeko/html-effectiveness"><img src="https://agentmods.dev/badge/skills/tincopper/neeko/html-effectiveness/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/tincopper/neeko/html-effectiveness"><img src="https://agentmods.dev/badge/skills/tincopper/neeko/html-effectiveness.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- 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 Rogue Agent · line 21 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
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 | $0.00142 | $0.03070 |
| Opus 5.5 | $0.00057 | $0.01228 |
| Sonnet 5.5 | $0.00028 | $0.00614 |
| Haiku 4.5 | $0.00014 | $0.00307 |
Grade A, and why
html-effectiveness 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 1mo 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 — 315 lines — stays where its author put it; the contents beside it link to each section on GitHub.
HTML Effectiveness: Interactive Output Engine
Core Principle
Markdown is a wall of text. HTML is a spatial, interactive document.
When you have multi-dimensional information to present, generate a single self-contained HTML file that users can explore, filter, compare, and interact with. The browser is the universal runtime - no build steps, no dependencies, no exports needed.
When to Use This Skill
Use HTML output when ANY of these are true:
- Comparing 2+ options with trade-offs (side-by-side cards)
- Presenting data with >5 rows (sortable/filterable table)
- Showing a timeline or sequence of events
- Explaining a concept with collapsible sections
- Reviewing code changes (annotated diffs)
- Presenting a plan with phases and dependencies
- Showing architecture or system design (boxes + arrows)
- Any output where the reader needs to SCAN, not read linearly
- Any output where the reader needs to CHOOSE between options
- Any output with tabular data, charts, or visual relationships
Use plain markdown when:
- Simple Q&A (one paragraph answer)
- Inline code fixes
- Brief status updates
- Sequential instructions (do X, then Y, then Z)
9 Output Patterns
Select the pattern that matches your information type:
1. Comparison Board
When: Evaluating approaches, tools, libraries, strategies Structure: Side-by-side cards with clear trade-offs, rating badges, recommendation highlight Interaction: Hover to highlight, click to expand details
2. Annotated Timeline
When: Incident post-mortems, project plans, history, implementation phases Structure: Vertical timeline with colored nodes, expandable details per step Interaction: Click nodes to expand/collapse, filter by category
3. Interactive Report
When: Status updates, analysis results, research findings Structure: Header stats, filterable sections, charts via inline SVG Interaction: Category filters, collapsible deep-dives, search
4. Code Review Board
When: PR reviews, refactoring proposals, architecture changes Structure: File-by-file cards with severity tags, before/after diffs, inline comments Interaction: Filter by severity, expand file details, toggle diff view
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.
- 1mo ago First seen · 315 lines · 142 tokens per session scan A 8743eb39a1e6
html-effectiveness is a skill published in the GitHub repository tincopper/neeko (12 stars, last pushed yesterday), licensed Apache-2.0. It adds 142 tokens to every session and 3,070 once invoked, about $0.0006 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 2026-08-31.
Other skills, from other repositories
sage-review
Deep, platform-neutral code review for PRs and CRs in ONE thorough single pass — design reasoning (Problem Worth Solving & Solution Fit) as one dimension alongside the 9 code-level dimensions, with chain-of-consequences, self-critique, and draft-only comments. The single app-owned source of truth.
design-critique
Run a heuristic evaluation of a UI design (image, HTML, Figma, URL, or flow) the way an experienced designer would. Evaluates 4 categories (Visual & hierarchy, Usability & interaction, Accessibility, Content) using recognized frameworks, NN/g 0-4 severity, and evaluability-aware prioritization that never judges what…
living-ui
Use when building an animated or interactive widget, explainer or dashboard page: how motion feels, where the eye goes, where words sit, reduced motion, keyboard and screen readers. Style-neutral: it never picks colours, fonts or shapes. Pairs with the widgets skill.
dashboard-template
Kiro Crew repo only: load this when a task will author or change a dashboard page. A page never ships alone: the same PR carries its TypedDict contract, its provider, and a parity test that the two agree. Scaffold all four from one field list; read numbers from an existing fold, never type them.
theme-pack-authoring
Build, validate, and install Kiro Crew theme packs -- pack anatomy, the 56-variable palette, role-tagged fonts, the overrides.css allowlist (what installs vs what actually renders), and the install-verify cycle. Use when the user wants to create or edit a theme pack.
image-authoring
Author images and diagrams as code — SVG, Pillow, Excalidraw, mermaid. Load when asked to draw, illustrate, or make an image, icon, logo, poster, or diagram.