# MCP tools reference (/references/mcp-tools) This page lists what the two [MCP servers](/overview/which-mcp-do-i-need) expose. Your agent discovers all of it on its own: you never call a tool by hand. Tool names that contain `custom_front` act on **data apps**, formerly called custom fronts. The names have not changed yet. ## Maker MCP [#maker-mcp] Server address: `https://toucanai.cloud/api/maker-mcp`. See [Build with an AI agent](/core/build/build-with-an-agent). ### Read your data and your organization [#read-your-data-and-your-organization] | Tool | What it does | | -------------------------- | ---------------------------------------------------------------------------------------------------------- | | `list_databases` | Lists the databases, tables and columns you can see, with the ids queries need. | | `run_data_query` | Runs a semantic query and returns the first 100 rows. Accepts `attributes` to preview as a given end user. | | `list_domains` | Lists your domains. | | `get_domain` | Reads a domain: tables, joins, dimensions, metrics and measures. | | `list_user_attributes` | Lists the user attributes your organization defines. | | `read_organization_memory` | Reads the organization's saved preferences, such as palette and chart conventions. | ### Model your data [#model-your-data] | Tool | What it does | | ---------------------------------------------------- | ----------------------------------------------------------------------------------- | | `find_domain_join_candidates` | Proposes the relationships that can join a domain's tables. | | `create_domain`, `update_domain` | Creates a domain, or renames it and adds tables and joins. Nothing is ever removed. | | `create_domain_measure`, `update_domain_measure` | Adds or changes a measure. | | `create_domain_dimension`, `update_domain_dimension` | Adds or changes a dimension. | | `create_domain_metric`, `update_domain_metric` | Adds or changes a metric. | ### Secure your data [#secure-your-data] | Tool | What it does | | ----------------------- | ---------------------------------------------------------------------- | | `define_user_attribute` | Declares a user attribute that access policies can use. | | `get_access_policy` | Reads a table's row-level and column-level policies. | | `preview_access_policy` | Shows, for sample users, what a policy change would do. Saves nothing. | | `apply_access_policy` | Applies a previewed change. Requires the preview's id. | ### Build data apps [#build-data-apps] Available if data apps are enabled for your organization. To have a team build them with you, see [Crew](/crew). | Tool | What it does | | ------------------------------------------------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `list_custom_fronts`, `get_custom_front`, `get_custom_front_version` | Lists data apps and reads one and its versions and files. | | `create_custom_front`, `update_custom_front`, `delete_custom_front` | Creates, renames or deletes a data app. Deleting is permanent. | | `create_custom_front_file`, `update_custom_front_file`, `patch_custom_front_file`, `delete_custom_front_file` | Changes the files of the draft version. | | `get_custom_front_upload_url` | Returns a 10-minute upload address and token, so an agent that can run a shell uploads files over HTTP instead of sending their content through the conversation. | | `commit_custom_front_version` | Freezes the draft and opens the next one. | | `publish_custom_front_version` | Serves a committed version to readers. | | `list_custom_front_store_entries`, `get_custom_front_store_entry`, `set_custom_front_store_entry`, `delete_custom_front_store_entry` | Manages the app's key-value store: targets, labels, thresholds. Changes apply immediately. | | `read_custom_front_sdk_reference` | Returns the reference of the SDK that data apps use. | ### Prompts [#prompts] | Prompt | What it does | | -------------------- | --------------------------------------------------------------------------------- | | `build_custom_front` | Builds a new data app: read your data, settle the query, write, preview, publish. | | `edit_custom_front` | Changes an existing data app. | | `secure_my_data` | Restricts rows and columns per end user, with a preview before applying. | ## Explorer MCP [#explorer-mcp] Server address: `https://toucanai.cloud/api/mcp`. See [Integrate Toucan into your own AI chat](/core/embed/embedding-overview/how-to/integrate-into-your-ai-chat). | Name | Type | What it does | | ---------------------- | ------ | --------------------------------------------------------------------------------------------------------------------------------------------- | | `ask_toucan_assistant` | Tool | Answers a data question. Takes `question` and an optional `threadId` to continue a conversation. Returns the answer, charts and a `threadId`. | | `tool-usage` | Prompt | Instructions to add to your chat's system prompt so it relays the answer as is. |