OnlyWorlds

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

• Connection: Runs in the cloud
• Transport: Streamable HTTP
• Category: Other
• You need to fill in: API-Key, API-Pin

Install

Pick the AI app you use, then copy the settings.

You need

• Runs in the cloudNothing to install; it connects over the internet

Which app do you use?

claude mcp add --transport http onlyworlds https://www.onlyworlds.com/mcp --header 'API-Key: your-value' --header 'API-Pin: your-value'

{
  "mcpServers": {
    "onlyworlds": {
      "url": "https://www.onlyworlds.com/mcp",
      "headers": {
        "API-Key": "your-value",
        "API-Pin": "your-value"
      }
    }
  }
}

{
  "servers": {
    "onlyworlds": {
      "type": "http",
      "url": "https://www.onlyworlds.com/mcp",
      "headers": {
        "API-Key": "your-value",
        "API-Pin": "your-value"
      }
    }
  }
}

Your choice stays on this device in a cookie; no account needed.

Values you fill in

• API-Key secret HTTP header
  A world's API key: an ow_w_ write key, an ow_r_ read key, an agent seat's key, or a legacy 10-digit key. The schema tools need no key.
• API-Pin secret HTTP header
  The PIN, needed for writes: your account PIN, or an agent seat's ow_s_ secret. Reads with an ow_w_ or ow_r_ key need no PIN.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Tool names and descriptions exactly as the server reported them on Nov 6, 2026. The maker wrote them, not us; we show them as plain text.

• list_element_types

  List all 22 OnlyWorlds element types with a one-line shape summary of each. Every world is built from these types; each element has a stable UUID `id`, a `name`, and a `type`. Use `get_element_schema(type)` for a type's full field list. Unauthenticated — schema is public referenc

• get_element_schema

  Return the field structure of one OnlyWorlds element `type` (a slug from `list_element_types`, e.g. "character"). The result groups the type's writable fields by kind so a caller knows how to read and write them: `text` (strings), `integer`, `single_link` (one UUID), `multi_link`

• search_schema

  Search every element type's fields for `query` (case-insensitive substring), across all 22 types. Useful for "which types have a `location` field?" or finding where a concept lives in the schema. Returns a mapping of type slug -> the matching field names in that type (types with

• list_worlds

  The worlds you can read here. With an API-Key: the key's one world. Signed in through a hosted client (a bearer), where this server offers one: every world your account owns or is a member of, as your account's world list shows them; pass one's `id` (or its `slug`) as `world` to

• list_elements

  List elements of one `type` in the world named by your API-Key header, newest-created first. `type` is a slug from `list_element_types` (e.g. "character"). Optional `name_contains` filters by case-insensitive name substring; `supertype` is trimmed and matched without regard to ca

• get_element

  Fetch one element by `type` and `id` (a UUID) from the world named by your API-Key header. `type` is a slug from `list_element_types`. Returns the full v2 wire shape (the same body as `GET /api/v2/{type}/{id}`): `type`, `id`, `name`, scalar fields, link fields as UUID arrays, and

• search_elements

  Search the world named by your API-Key header for elements whose name or text fields (description and each type's prose fields, such as a Character's background) hold every word of `query` as a whole word, ignoring case: "ore" does not find "more", and "copper mine" needs both wo

• get_changes

  Return the delta feed for the world named by your API-Key header: every element created/updated (`op: "upsert"`, full body) or deleted (`op: "delete"`) since `since_cursor`, in apply order, in pages of `limit` (default 25, max 1000). Entries carry FULL element bodies — a default

• get_draught

  What one Character knows, in one read: the draught. `id` is the Character's UUID; `policy` is one JSON object, every key optional: `components` (a list, or a comma string, of self, role, work, style, events, knowledge, names, sheet, recent, messages, room, proposed, roster; defau

• list_files

  List the files attached to one element (`type` and `id`, a UUID) in the world named by your API-Key header: PDFs, text files and world bundles kept on onlyworlds.com beside the element, never inside it. Returns `{data: [{id, name, kind, size, label, added_by, added_at}, ...]}`, n

• read_file

  Read one file attached to an element, by its id (from `list_files`). A text file (txt, md, json, csv, yaml, toml) answers its words, at most 64 KB per call (`truncated: true` past that), in `text`, which always begins with one line saying who added it and when, and that a file is

• create_element

  Create one new element of `type` in the world named by your API-Key header. `type` is a slug from `list_element_types` (e.g. "character"). `element` is the field payload: `name` plus any scalar, link, or extension fields for that type (call `get_element_schema(type)` for the fiel

• update_element

  Update an existing element by `type` and `id`, changing ONLY the fields you pass — omitted fields are preserved. This is a server-side read-merge: the current element is loaded and only the keys in `fields` are applied, so it is safe against the raw-HTTP-PATCH hazard where sendin

• edit_links

  Add and/or remove links on ONE multi-link `field` of an element, leaving the rest of that field's array untouched. Use this for additive/subtractive link edits (unlike `update_element`, which REPLACES a link array). `type` is a slug from `list_element_types`; `id` is the element'

• bulk_apply

  Create and/or update many elements across any of the 22 types in one call. Each entry in `items` is `{"type": , "element": }` with the same payload shape `create_element` takes: an `element` with an `id` UPDATES that id (creating it if absent), an `element` without an `id` CREATE

• get_image_upload_ticket

  Get a ticket to upload ONE image into this world, for an element's `image_url` (Keel #59). The image never passes through this tool: you send its bytes yourself, straight to the image host, with the ticket. Steps: 1. Call this tool. You get `ticket`, `upload_url`, `max_bytes` and

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 6, 2026

• ! Caution

  Maker matches the repo

  The registry lists no source repo, so we cannot match the publisher (onlyworlds.com) to the code

• … Not checked yet

  Still maintained

  We have not read this repo from GitHub yet

• … Not checked yet

  Has a licence

  We have not read this repo from GitHub yet

• ✓ Pass

  Endpoint responds

  Responded in 114 ms (HTTP 200)

• – Not applicable

  Sign-in with OAuth

  No sign-in needed

• ✓ Pass

  No hidden instructions in tool descriptions

  Read 16 tool descriptions and found no hidden instructions to the AI

Compared with others in Otheri

• More stars than 0% of the other 32505 servers in this category
• Published to the registry more recently than 91% of the other 32505 servers in this category
• Basic checks equal to or better than 37% of the other 32505 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

README from the maker

No README found in the repo