three.ws: Skill for Claude Code

Build a three.ws agent skill

A three.ws skill is a directory served from any URL. The agent runtime fetches it, injects its instructions into the system prompt, exposes its tools to the LLM, and runs its handlers in a Web Worker sandbox. Because a skill is just files behind a URL, the same bundle installs into every agent without copying code.

Do not confuse this with the Claude skill you are reading: that one teaches an external model how to use three.ws. This one teaches a three.ws agent a new capability.

The four files

File	Required	Purpose
manifest.json	yes	Identity, version, what it provides, config defaults
SKILL.md	yes	Instructions injected into the agent's system prompt
tools.json	yes, if it exposes tools	JSON Schema tool definitions the LLM can call
handlers.js	no	ES module implementing each tool

A bundle with no handlers.js is valid and always trusted: it is a declarative skill that only shapes behavior (an accent, a house style, a refusal policy).

Assets (clips/, morphs/, prompts/, assets/) sit beside those files and are resolved against ctx.skillBaseURI.

A complete, working bundle

Copy this shape. The repo's starter is examples/skills/wave/ and the runtime contract is docs/skills.md.

manifest.json

{
  "spec": "skill/0.1",
  "name": "weather-report",
  "version": "0.1.0",
  "description": "Look up the current temperature and wind for any named place and say it out loud.",
  "license": "MIT",
  "tags": ["weather", "voice"],
  "requires": { "runtime": ">=0.1.0", "capabilities": [] },
  "provides": { "tools": ["reportWeather"], "triggers": [] },
  "config": { "units": "metric" }
}

tools.json

{
  "tools": [
    {
      "name": "reportWeather",
      "description": "Report the current temperature and wind speed for a named place, and speak the result.",
      "input_schema": {
        "type": "object",
        "properties": {
          "place": { "type": "string", "description": "City, town, or landmark name" }
        },
        "required": ["place"]
      }
    }
  ]
}