WritingmateWritingmate Documentation

MCP Integration

What MCP servers do

Model Context Protocol (MCP) is a standard that lets a supported AI model use tools from an outside service. A connected MCP server can provide tools for an API, database, automation platform, or business app.

Writingmate supports MCP in two directions:

  • Connect an outside MCP server to Writingmate, then select its tools in chat.
  • Connect an external MCP host to Writingmate's own MCP server, using OAuth 2.1 or a Writingmate Developer Key.

Use Writingmate as an MCP Server

Writingmate can also be connected to external MCP hosts as a remote MCP server. This is useful when an agent client supports MCP and you want it to call Writingmate model and generation tools.

SettingValue
MCP server URLhttps://writingmate.ai/api/mcp
AuthenticationOAuth 2.1 (recommended) or a Writingmate Developer Key
Protected resource metadatahttps://writingmate.ai/.well-known/oauth-protected-resource/api/mcp

The Writingmate MCP server exposes tools for:

  • listing Writingmate models
  • retrieving model metadata
  • creating OpenAI-compatible chat completions
  • creating OpenAI-compatible Responses API responses
  • generating images
  • starting and polling video generations

For an MCP host that supports OAuth, add only the MCP server URL. The host discovers Writingmate's authorization server, opens a browser for sign-in and consent, and manages the access and refresh tokens. You do not need to copy a Developer Key into the host.

OAuth uses the authorization code flow with PKCE. PKCE protects the temporary authorization code from being used by another app. Writingmate also supports dynamic client registration for MCP hosts that register themselves during setup.

Use a Developer Key when your MCP host supports a fixed bearer token instead of OAuth. A Developer Key is a password-like token that lets another app use your Writingmate account.

Test initialization with cURL:

curl https://writingmate.ai/api/mcp \
  -H "Authorization: Bearer YOUR_WRITINGMATE_DEVELOPER_KEY" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{
    "jsonrpc": "2.0",
    "id": "init",
    "method": "initialize",
    "params": {
      "protocolVersion": "2025-11-25",
      "capabilities": {},
      "clientInfo": { "name": "my-agent-client", "version": "1.0.0" }
    }
  }'

For static bearer authentication, create a Writingmate Developer Key in Profile Settings → API Keys. OAuth and Developer Key requests use the same plan access, workspace, and usage limits as the OpenAI-compatible API.

Open MCP Integration settings

  1. Sign in to Writingmate.
  2. Open your profile menu and select Profile Settings.
  3. Select MCP Integration in the settings sidebar.

The page title is Model Context Protocol. It has two tabs:

  • Integrations is the standard setup view for adding servers, checking connection status, and reviewing discovered tools.
  • JSON Editor is the advanced view for editing the full mcpServers configuration.

You can also open MCP Integration settings directly.

Connect a remote MCP server

Use the Integrations tab for a remote server that provides an MCP URL:

  1. Select Add MCP Server.
  2. Enter a Server Name. Use letters, numbers, underscores, or hyphens.
  3. Paste the remote endpoint into MCP Server URL.
  4. Select Add Server.
  5. Review the server card. Writingmate shows Connected, Needs Authentication, or Connection Issue.
  6. If the card shows Needs Authentication, select Connect and complete the provider's authorization window.

Writingmate uses Streamable HTTP for servers added through this form. After a successful save or OAuth connection, it refreshes the server's available tools automatically.

Only connect servers you trust. MCP tools can read data or perform actions allowed by the outside service. Review the selected tools before asking a model to use them.

Connect Zapier MCP

The Integrations tab includes Connect to 8000+ tools with Zapier until a Zapier server is configured.

  1. In Zapier MCP, create an MCP server.
  2. Choose Other as the client if Writingmate is not listed.
  3. Add and configure the Zapier actions that you want the model to use.
  4. Copy the server's connection URL from Zapier.
  5. In Writingmate, paste it into Zapier MCP URL.
  6. Select Connect to Zapier.
  7. If Writingmate shows Needs Authentication, select Connect and complete the authorization window.

Zapier currently requires Streamable HTTP for MCP clients. See the Zapier MCP quickstart for Zapier's current server and tool setup.

Use the JSON Editor

Use JSON Editor when you need custom headers, an explicit transport, or a command-based server configuration.

  1. Open JSON Editor, or select Advanced JSON Editor from the Integrations tab.
  2. Edit the MCP Configuration JSON.
  3. Select Validate JSON to check the JSON syntax.
  4. Select Save Configuration to validate the full MCP schema and save it.

The root object must contain mcpServers. Each named server must use either url or command, but not both. URL-based servers can use streamable_http or sse; Streamable HTTP is preferred when the provider supports it.

Saving the JSON updates the Integrations tab and refreshes the discovered tools. Do not place credentials in this documentation or in chat. Store any provider authorization header only in your private MCP configuration.

Connect Ahrefs MCP

Ahrefs supports OAuth and manually generated MCP keys at its hosted Streamable HTTP endpoint:

https://api.ahrefs.com/mcp/mcp

For OAuth, add that URL through Add MCP Server, save it, then select Connect when Writingmate shows Needs Authentication.

For an MCP key, use the JSON Editor and add the key as an authorization header:

{
  "mcpServers": {
    "ahrefs": {
      "url": "https://api.ahrefs.com/mcp/mcp",
      "transport": "streamable_http",
      "headers": {
        "Authorization": "Bearer YOUR_AHREFS_MCP_TOKEN"
      }
    }
  }
}

Use the MCP key generated by Ahrefs for YOUR_AHREFS_MCP_TOKEN. Do not substitute another Ahrefs key unless your Ahrefs plan explicitly supports it. See the official Ahrefs MCP documentation for current account requirements and authorization options.

Use connected tools in chat

After Writingmate discovers the server's tools:

  1. Start a signed-in chat with a text model that supports tools.
  2. Select the + button beside the message box. Its label is Add content or tools.
  3. Open Integrations.
  4. Select the server to enable all of its tools, or open its submenu and select individual tools.
  5. Ask the model to use the connected service.

The submenu shows No integrations configured until Writingmate discovers at least one server. In an Agent chat, only the MCP tools configured for that Agent appear.

Manage or remove a server

The Integrations tab shows the server URL, connection status, and discovered tool count.

  • Select View All on a connected Zapier server to review its discovered tools.
  • Select Edit to change a Zapier server URL.
  • Select Remove, then confirm Delete Server, to remove a server and its saved configuration.

Usage and provider charges

The model request that calls an MCP tool uses your normal Writingmate message allowance. The outside service can also apply its own permissions, rate limits, usage allowance, or charges.

See Message Limits for Writingmate usage counting.

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