OnlyWorlds tools

The list of tools built on OnlyWorlds, and how a tool gets on it.

Anyone can build a tool on OnlyWorlds today, with no sign-up: the API, the SDKs (npm, PyPI) and the docs are public. This repository is for being listed: we read your tool against a short checklist, and a row here says what we read and when.

List your tool → · what it means, in full: List your tool

Three rungs

Rung	What it means	Who decides
Built on OnlyWorlds	reads or writes worlds through the API, world folders or MCP, and names itself (a client name, an x_<tool>_ prefix)	nobody: a convention anyone may follow
Listed	read against the checklist below, every line passed, on a date	the OnlyWorlds maintainer, on each tool
Signed in	a person can sign in to it with their OnlyWorlds account	the maintainer, per tool, after it is listed

Nothing is signed in that is not listed, and nothing is listed that is not built.

The checklist

1. It is what it says. The URL serves the tool; the source is public, or the submission says why not.
2. Keys stay with the person. The key and PIN are stored on the person's device or in their own environment, never on the tool's server.
3. It names itself. A client name on its writes, an x_<tool>_ prefix for its own fields (Atlas keeps its older atlas_, which the server keeps as written), the producer line on folders it makes.
4. It speaks the wire. Its calls are ones the API document describes; a folder it writes passes the folder lint; an .owworld it writes opens in the reference reader.
5. It is honest about what leaves the machine. One sentence: what world data goes where.
6. The host answers, read from outside, signed out: https and its certificate, no dangling name, the hosts its first page loads from.
7. Its core is open and free. What the tool is for works for anyone, without paying and without an invite. Extras may cost.

Lines 2 and 5 cannot be seen from outside: a row marks them claimed, or read in source when the source is public and we read it. Every line carries the date it was read. What the list does not claim: that a tool is good, safe beyond these lines, or maintained.

The file

tools.json is the list. A site that shows it copies it in at build time, never fetches it from GitHub in a browser. Only the maintainers write it, on a person's reading of each submission; node check.mjs checks its shape, and CI runs it on every push.

{
  "format": 1,
  "tools": [
    {
      "id": "mytool",                       // [a-z0-9-], 1 to 32, unique
      "name": "My Tool",
      "sentence": "What it does for a person.",
      "url": "https://mytool.example",      // https, unique
      "source": "https://github.com/me/mytool",  // or null, with source_note saying why
      "source_note": null,
      "maker": "Who answers for it",
      "doors": ["api", "folder"],           // any of api, folder, owworld, mcp
      "client": "mytool",                   // its X-OW-Client name, or null; unique
      "prefix": "x_mytool_",                // its own fields' prefix (x_<tool>_; atlas_ for Atlas), or null
      "free_core": "What anyone can do for free.",
      "paid": "What costs, or null.",
      "rung": "listed",                     // built | listed | delisted
      "listed_on": "2026-10-20",            // listed and delisted rows
      "listed_by": "the maintainer's word, where it was given",
      "delisted_on": null,                  // delisted rows: a delisted row stays, with its date
      "delisted_why": null,
      "submission": "https://github.com/OnlyWorlds/tools/issues/1",
      "checks": {                           // the seven lines; a listed row answers all, each a pass
        "what_it_says":    { "result": "pass", "how": "read", "on": "2026-10-20" },
        "keys_stay":       { "result": "pass", "how": "read in source", "on": "2026-10-20" },
        "names_itself":    { "result": "pass", "how": "read", "on": "2026-10-20" },
        "speaks_the_wire": { "result": "pass", "how": "read", "on": "2026-10-20" },
        "what_leaves":     { "result": "pass", "how": "claimed", "on": "2026-10-20", "note": "Nothing leaves the browser." },
        "host":            { "result": "pass", "how": "read", "on": "2026-10-20" },
        "free_core":       { "result": "pass", "how": "read", "on": "2026-10-20" }
      }
    }
  ]
}

Every key is present (null when it does not apply); a key the check does not know is refused by name. What a later read of a tool's host finds is shown beside its row, never written into this file.