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 agentmods add instructions/tryopendata/skills/claude-mdgit clone --depth 1 https://github.com/tryopendata/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/instructions/tryopendata/skills/claude-md)<a href="https://agentmods.dev/instructions/tryopendata/skills/claude-md"><img src="https://agentmods.dev/badge/instructions/tryopendata/skills/claude-md.svg" alt="Measured on agentmods" 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 | $0.01192 | $0.01192 |
| Opus 5 | $0.00596 | $0.00596 |
| Sonnet 5 | $0.00238 | $0.00238 |
| Haiku 4.5 | $0.00119 | $0.00119 |
Grade A, and why
skills CLAUDE.md 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 4d 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 — 145 lines — stays where its author put it; the contents beside it link to each section on GitHub.
OpenData Skills
Cross-platform agent skills repo following the Agent Skills specification.
Plugins
This repo contains multiple independently installable plugins:
| Plugin | Namespace | Source | Skills |
|---|---|---|---|
| opendata | opendata |
plugins/opendata/ |
opendata-api |
| openchart | openchart |
plugins/openchart/ |
openchart |
| opendesign | opendesign |
plugins/opendesign/ |
svg-design |
Each plugin has its own plugins/<name>/.claude-plugin/plugin.json for metadata. The root .claude-plugin/marketplace.json registers all plugins.
Directory Structure
.claude-plugin/
marketplace.json # root marketplace registry (all plugins)
plugins/
opendata/
.claude-plugin/plugin.json
skills/
opendata-api/
commands/ # when needed
agents/ # when needed
openchart/
.claude-plugin/plugin.json
skills/
openchart/
opendesign/
.claude-plugin/plugin.json
skills/
svg-design/
Adding a Skill
- Create
plugins/<plugin>/skills/<name>/SKILL.mdwith YAML frontmatter:
---
name: my-skill-name
description: >
What this skill does and when to use it. Use imperative phrasing
like "Use when..." Max 1024 chars.
---
-
namefield: lowercase letters, numbers, hyphens only. Max 64 chars. Must match the parent directory name. No leading/trailing/consecutive hyphens. -
descriptionfield: Describe what and when. Use imperative phrasing ("Use when..."). Focus on user intent, not implementation. Max 1024 chars. -
Optional frontmatter:
license,compatibility,metadata(key-value map),allowed-tools(space-delimited) -
Body: Instructions for the agent. Keep under 500 lines / 5000 tokens. Split large content into
references/files and reference them conditionally ("Readreferences/api-errors.mdif the API returns a non-200 status").
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.
- 4d ago First seen · 145 lines · 1,192 tokens per session scan A 450fcf90654c
skills CLAUDE.md is an instructions file published in the GitHub repository tryopendata/skills (127 stars, last pushed 1mo ago), licensed MIT. It adds 1,192 tokens to every session, about $0.0060 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.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
next.js AGENTS.md
Instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.