Reference

Tool Catalog

All Stitch tools available to agents — schemas, return types, and parameter details.

Tool Catalog

Every tool available through the Stitch MCP server. Upstream tools come directly from the Stitch API. Virtual tools are added by the proxy and combine multiple API calls into single operations.

Upstream tools

Available in both proxy and direct connection modes.

Tool	Description
`list_projects`	List all Stitch projects accessible to the user
`get_project`	Get details for a specific project by resource name
`list_screens`	List all screens within a project
`get_screen`	Get details for a specific screen (metadata, download URLs)
`generate_screen_from_text`	Generate a new screen from a text prompt
`edit_screens`	Edit existing screens using a text prompt
`generate_variants`	Generate design variants of existing screens

Virtual tools

Available only through the proxy. See Connection Modes for proxy vs direct.

`build_site`

Builds a site from a project by mapping screens to routes. Returns the design HTML for each page.

Input schema:

JSON

{
  "projectId": "string (required)",
  "routes": [
    {
      "screenId": "string (required)",
      "route": "string (required, e.g. \"/\" or \"/about\")"
    }
  ]
}

Returns: An object with success, pages (array of { screenId, route, title, html }), and message.

`get_screen_code`

Retrieves a screen and downloads its HTML code content.

Input schema:

JSON

{
  "projectId": "string (required)",
  "screenId": "string (required)"
}

Returns: The screen object with an added htmlContent field containing the full HTML source.

`get_screen_image`

Retrieves a screen and downloads its screenshot image as base64.

Input schema:

JSON

{
  "projectId": "string (required)",
  "screenId": "string (required)"
}

Returns: The screen object with an added screenshotBase64 field containing a base64-encoded PNG.

`list_tools`

Lists all available tools with their descriptions and schemas.

Input schema: No parameters.

Returns: An array of tool objects with name, description, and inputSchema.

Common parameter mistakes

Forgetting projectId: Every screen-level tool requires a projectId. Use list_projects first if you don’t have one.

Screen name vs screen ID: The screenId parameter expects the screen’s ID (e.g., 98b50e2ddc9943efb387052637738f61), not its display name. Use list_screens to find screen IDs.

Duplicate routes in build_site: Each route path must be unique. The tool validates this and returns an error if duplicates are found.

Missing screens: If a screenId doesn’t exist in the project, build_site returns an error listing the missing IDs. Verify screen IDs with list_screens first.