MCP tools reference

Every tool and prompt exposed by the Maker MCP and the Explorer MCP, with what each one does.

This page lists what the two MCP servers 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

Server address: https://toucanai.cloud/api/maker-mcp. See Build with an AI agent.

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.

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.

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.

Available if data apps are enabled for your organization. To have a team build them with you, see 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.

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.

Server address: https://toucanai.cloud/api/mcp. See Integrate Toucan into your own 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.