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PopNx MCPMCP servers for people who use AI · explained in plain words

OnlyWorlds

by onlyworlds.comversion 1.0.1i★ –iRuns in the cloud
Registry namecom.onlyworlds/mcp

How to install

What it does

Read and write typed fictional worlds (22 linked element types) via the OnlyWorlds open standard.

  • Connects Runs in the cloud
  • Account or key Works without a key · add API-Key, API-Pin if you have one (often raises limits)
  • Category Other

Install

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

Passed 2/3 checks · What you ask goes through the maker’s server (www.onlyworlds.com) · ✓ Commands checked Nov 13, 2026

First: which AI do you use?

Pick your app and the steps appear below.

Works with Claude · about 2 min

No key, nothing to install · Set it up once on claude.ai or the desktop app, then use it in chat · free accounts can add 1 · on Team/Enterprise an Owner adds it

  1. Open Claude’s Connectors page

    CustomizeConnectors

    CustomizeConnectors1Add2https://…3Add4
  2. Click “Add” → “Custom” → “Web” and fill in these 2 fields

    Copy each value into the field with the same name in Claude, then click Continue

    Name · NameOnlyWorlds
    Remote MCP server URL · Addresshttps://www.onlyworlds.com/mcp

    Click Continue past the sign-in settings Claude detected · under Authentication choose what the maker says (Sign in now, Sign in when needed or No sign in), then click Add

  3. Turn it on in a chat

    +ConnectorsOnlyWorlds

  4. Try it

    Use OnlyWorlds and tell me what you can do for me, then show me one thing

    ✓ If Claude says it is using OnlyWorlds or shows a OnlyWorlds tool in the answer, you are connected

Menu names checked against Anthropic’s help page on Nov 11, 2026 · your screen may differ slightly by app version

Works with ChatGPT, depending on your plan

Full MCP: ChatGPT Business, Enterprise or Edu on the web · Pro: connects with read/fetch permissions, so tools that change data may not work · Plus: not confirmed in OpenAI’s docs; if you see an add-custom-MCP option on the Plugins page you can try these steps · web only

  1. Open ChatGPT’s add-MCP page on the web

    Plugins+Add custom MCP server

    ChatGPTPlugins1+2https://…3Create4
  2. Fill in the name and address

    Enter a name, paste the address under Connection, tick the risk warning and click Create as a plugin

    Name · NameOnlyWorlds
    Connection · Addresshttps://www.onlyworlds.com/mcp
  3. Pick OnlyWorlds in a chat

    Start a new chat and pick OnlyWorlds from your plugins before typing

  4. Try it

    Use OnlyWorlds and tell me what you can do for me, then show me one thing

    ✓ If ChatGPT says it is using OnlyWorlds or shows a OnlyWorlds tool in the answer, you are connected

Menu names checked against OpenAI’s help page on Nov 11, 2026 · your screen may differ slightly by app version

Works with Claude Code · about 2 min

No key, nothing to install

  1. Open Terminal

    Mac: press Command+Space and type Terminal · Windows: open PowerShell

  2. Paste this command and press Enter

    claude mcp add --transport http --scope user onlyworlds https://www.onlyworlds.com/mcp
  3. Type /mcp in Claude Code

    You should see OnlyWorlds listed as connected

  4. Try it

    Use OnlyWorlds and tell me what you can do for me, then show me one thing

    ✓ If Claude Code says it is using OnlyWorlds or shows a OnlyWorlds tool in the answer, you are connected

Menu names checked against Anthropic’s help page on Nov 11, 2026 · your screen may differ slightly by app version

Works with Cursor · about 2 min

No key, nothing to install

  1. Click this button to open Cursor

    Open in Cursor

    Cursor asks you to confirm; click Install

  2. Open the AI chat in Cursor in Agent mode

  3. Try it

    Use OnlyWorlds and tell me what you can do for me, then show me one thing

    ✓ If Cursor says it is using OnlyWorlds or shows a OnlyWorlds tool in the answer, you are connected

Menu names checked against Cursor’s help page on Nov 11, 2026 · your screen may differ slightly by app version

Works with VS Code · about 2 min

No key, nothing to install

  1. Click this button to open VS Code

    Open in VS Code

    VS Code asks you to confirm; click Install

  2. Open the AI chat in VS Code in Agent mode

  3. Try it

    Use OnlyWorlds and tell me what you can do for me, then show me one thing

    ✓ If VS Code says it is using OnlyWorlds or shows a OnlyWorlds tool in the answer, you are connected

Menu names checked against VS Code’s help page on Nov 11, 2026 · your screen may differ slightly by app version

Other apps that use MCP, such as Windsurf, Zed or Gemini CLI, each add servers differently. See how in the app list.

See every app that uses MCP →

Address for apps that connect over the web

Addresshttps://www.onlyworlds.com/mcp

JSON settings are under “For developers” below

Stuck? Ask people who use OnlyWorlds💬 Discussion →
For developers: Terminal commands and JSON settings

Over the web

Claude Code

claude mcp add --transport http --scope user onlyworlds https://www.onlyworlds.com/mcp

Cursor (~/.cursor/mcp.json)

{
  "mcpServers": {
    "onlyworlds": {
      "url": "https://www.onlyworlds.com/mcp"
    }
  }
}

VS Code (mcp.json)

{
  "servers": {
    "onlyworlds": {
      "type": "http",
      "url": "https://www.onlyworlds.com/mcp"
    }
  }
}

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.

Descriptions are as written by the maker.

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

At a glance

Downloads per weeki
Not on npm/PyPI
Verified domain
✓ onlyworlds.com
Licencei
No licence stated
Connection
Runs in the cloud
Transport
streamable-http
Latest versioni
1.0.1
Categoryi
Other
Published to registryi
Nov 3, 2026
Code last changedi
–
Maker
onlyworlds.com
Repo
–
Registry status
Active

Which apps can use it

Based on how this server connects and on each app’s own docs, checked Nov 10, 2026.

Connect over the internet in

ClaudeChatGPTGooseLM StudioMsty StudioCherry StudioCursorVS Code + GitHub CopilotVisual StudioWindsurf (Devin Desktop)ZedKiroClineContinueJetBrains AI AssistantClaude CodeCodex CLIGemini CLIOpenCodenodecodeWarpLibreChatOpen WebUIRaycast

All apps, with pros and cons →

Related guides

What it can do

Tool names and descriptions exactly as the server reported them on Nov 11, 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, images (png, jpg, webp, avif) and world bundles kept on onlyworlds.com beside the element, never inside it. Returns `{data: [{id, name, kind, size, label,

  • 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 kept. This is the same partial update as `PATCH /api/v2/{type}/{id}`: each field you pass replaces that field's value whole. A text field you pass is set (pass an empty string `""

  • 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 14, 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 206 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

Discussion

Ask, share a tip or report that it does not work. Sorted by what people marked helpful.

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User reviews

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Compared with others in Otheri

  • More stars than 0% of the other 19774 servers in this category
  • Published to the registry more recently than 80% of the other 19774 servers in this category
  • Basic checks equal to or better than 45% of the other 19774 servers in this category

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

Common questions

Is OnlyWorlds safe?

It passed 2 of 3 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

The registry does not list a required key, though some servers ask you to sign in on first use.

Does it run on my computer or in the cloud?

It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.0.1) reached the registry 11 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT on the web (full MCP on Business and above; Pro read-only).

What can I use instead?

In the same category: World Monitor, Claude Flow, Windmill

Others in the same category

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

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

World Monitor

Real-time global intelligence on conflict, markets, energy, trade, shipping and cyber. 99 tools.

by koala73Widely used★ 90.6KUpdated today

Runs in the cloud✓ service owner · worldmonitor.app

Claude Flow

AI orchestration with hive-mind swarms, neural networks, and 87 MCP tools for enterprise dev.

by ruvnetWidely used↓ 13.5K/wk★ 81.7KUpdated 14 months ago

Runs on your computer

Windmill

Run Windmill scripts and flows and manage jobs, schedules, resources and variables.

by windmill-labsWidely used★ 18.6KUpdated 2 days ago

Runs in the cloud

README from the maker

No README found in the repo