# Tools ## Delete Tool **delete** `/v1/tools/{tool_id}` Delete a tool by name ### Path Parameters - `tool_id: string` The ID of the tool in the format 'tool-' ### Example ```http curl https://api.letta.com/v1/tools/$TOOL_ID \ -X DELETE \ -H "Authorization: Bearer $LETTA_API_KEY" ``` #### Response ```json {} ``` ## Retrieve Tool **get** `/v1/tools/{tool_id}` Get a tool by ID ### Path Parameters - `tool_id: string` The ID of the tool in the format 'tool-' ### Returns - `Tool object { id, args_json_schema, created_by_id, 15 more }` Representation of a tool, which is a function that can be called by the agent. - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` ### Example ```http curl https://api.letta.com/v1/tools/$TOOL_ID \ -H "Authorization: Bearer $LETTA_API_KEY" ``` #### Response ```json { "id": "tool-123e4567-e89b-12d3-a456-426614174000", "args_json_schema": { "foo": "bar" }, "created_by_id": "created_by_id", "default_requires_approval": true, "description": "description", "enable_parallel_execution": true, "json_schema": { "foo": "bar" }, "last_updated_by_id": "last_updated_by_id", "metadata_": { "foo": "bar" }, "name": "name", "npm_requirements": [ { "name": "x", "version": "version" } ], "pip_requirements": [ { "name": "x", "version": "version" } ], "project_id": "project_id", "return_char_limit": 1, "source_code": "source_code", "source_type": "source_type", "tags": [ "string" ], "tool_type": "custom" } ``` ## Update Tool **patch** `/v1/tools/{tool_id}` Update an existing tool ### Path Parameters - `tool_id: string` The ID of the tool in the format 'tool-' ### Body Parameters - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `default_requires_approval: optional boolean` Whether or not to require approval before executing this tool. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function (auto-generated from source_code if not provided) - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. ### Returns - `Tool object { id, args_json_schema, created_by_id, 15 more }` Representation of a tool, which is a function that can be called by the agent. - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` ### Example ```http curl https://api.letta.com/v1/tools/$TOOL_ID \ -X PATCH \ -H 'Content-Type: application/json' \ -H "Authorization: Bearer $LETTA_API_KEY" \ -d '{}' ``` #### Response ```json { "id": "tool-123e4567-e89b-12d3-a456-426614174000", "args_json_schema": { "foo": "bar" }, "created_by_id": "created_by_id", "default_requires_approval": true, "description": "description", "enable_parallel_execution": true, "json_schema": { "foo": "bar" }, "last_updated_by_id": "last_updated_by_id", "metadata_": { "foo": "bar" }, "name": "name", "npm_requirements": [ { "name": "x", "version": "version" } ], "pip_requirements": [ { "name": "x", "version": "version" } ], "project_id": "project_id", "return_char_limit": 1, "source_code": "source_code", "source_type": "source_type", "tags": [ "string" ], "tool_type": "custom" } ``` ## List Tools **get** `/v1/tools/` Get a list of all tools available to agents. ### Query Parameters - `after: optional string` Cursor for pagination (tool ID). Returns results relative to this ID in the specified sort order. Expected format: 'tool-' - `before: optional string` Cursor for pagination (tool ID). Returns results relative to this ID in the specified sort order. Expected format: 'tool-' - `exclude_tool_types: optional array of string` Tool type(s) to exclude - accepts repeated params or comma-separated values - `limit: optional number` Maximum number of tools to return - `name: optional string` Filter by single tool name - `names: optional array of string` Filter by specific tool names - `order: optional "asc" or "desc"` Sort order for tools by creation time. 'asc' for oldest first, 'desc' for newest first - `"asc"` - `"desc"` - `order_by: optional "created_at"` Field to sort by - `"created_at"` - `return_only_letta_tools: optional boolean` Return only tools with tool_type starting with 'letta_' - `search: optional string` Search tool names (case-insensitive partial match) - `tool_ids: optional array of string` Filter by specific tool IDs - accepts repeated params or comma-separated values - `tool_types: optional array of string` Filter by tool type(s) - accepts repeated params or comma-separated values ### Returns - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` ### Example ```http curl https://api.letta.com/v1/tools/ \ -H "Authorization: Bearer $LETTA_API_KEY" ``` #### Response ```json [ { "id": "tool-123e4567-e89b-12d3-a456-426614174000", "args_json_schema": { "foo": "bar" }, "created_by_id": "created_by_id", "default_requires_approval": true, "description": "description", "enable_parallel_execution": true, "json_schema": { "foo": "bar" }, "last_updated_by_id": "last_updated_by_id", "metadata_": { "foo": "bar" }, "name": "name", "npm_requirements": [ { "name": "x", "version": "version" } ], "pip_requirements": [ { "name": "x", "version": "version" } ], "project_id": "project_id", "return_char_limit": 1, "source_code": "source_code", "source_type": "source_type", "tags": [ "string" ], "tool_type": "custom" } ] ``` ## Create Tool **post** `/v1/tools/` Create a new tool ### Body Parameters - `source_code: string` The source code of the function. - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `default_requires_approval: optional boolean` Whether or not to require approval before executing this tool. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function (auto-generated from source_code if not provided) - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_type: optional string` The source type of the function. - `tags: optional array of string` Metadata tags. ### Returns - `Tool object { id, args_json_schema, created_by_id, 15 more }` Representation of a tool, which is a function that can be called by the agent. - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` ### Example ```http curl https://api.letta.com/v1/tools/ \ -H 'Content-Type: application/json' \ -H "Authorization: Bearer $LETTA_API_KEY" \ -d '{ "source_code": "source_code" }' ``` #### Response ```json { "id": "tool-123e4567-e89b-12d3-a456-426614174000", "args_json_schema": { "foo": "bar" }, "created_by_id": "created_by_id", "default_requires_approval": true, "description": "description", "enable_parallel_execution": true, "json_schema": { "foo": "bar" }, "last_updated_by_id": "last_updated_by_id", "metadata_": { "foo": "bar" }, "name": "name", "npm_requirements": [ { "name": "x", "version": "version" } ], "pip_requirements": [ { "name": "x", "version": "version" } ], "project_id": "project_id", "return_char_limit": 1, "source_code": "source_code", "source_type": "source_type", "tags": [ "string" ], "tool_type": "custom" } ``` ## Upsert Tool **put** `/v1/tools/` Create or update a tool ### Body Parameters - `source_code: string` The source code of the function. - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `default_requires_approval: optional boolean` Whether or not to require approval before executing this tool. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function (auto-generated from source_code if not provided) - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_type: optional string` The source type of the function. - `tags: optional array of string` Metadata tags. ### Returns - `Tool object { id, args_json_schema, created_by_id, 15 more }` Representation of a tool, which is a function that can be called by the agent. - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` ### Example ```http curl https://api.letta.com/v1/tools/ \ -X PUT \ -H 'Content-Type: application/json' \ -H "Authorization: Bearer $LETTA_API_KEY" \ -d '{ "source_code": "source_code" }' ``` #### Response ```json { "id": "tool-123e4567-e89b-12d3-a456-426614174000", "args_json_schema": { "foo": "bar" }, "created_by_id": "created_by_id", "default_requires_approval": true, "description": "description", "enable_parallel_execution": true, "json_schema": { "foo": "bar" }, "last_updated_by_id": "last_updated_by_id", "metadata_": { "foo": "bar" }, "name": "name", "npm_requirements": [ { "name": "x", "version": "version" } ], "pip_requirements": [ { "name": "x", "version": "version" } ], "project_id": "project_id", "return_char_limit": 1, "source_code": "source_code", "source_type": "source_type", "tags": [ "string" ], "tool_type": "custom" } ``` ## Search Tools **post** `/v1/tools/search` Search tools using semantic search. Requires tool embedding to be enabled (embed_tools=True). Uses vector search, full-text search, or hybrid mode to find tools matching the query. Returns tools ranked by relevance with their search scores. ### Body Parameters - `limit: optional number` Maximum number of results to return. - `query: optional string` Text query for semantic search. - `search_mode: optional "vector" or "fts" or "hybrid"` Search mode: vector, fts, or hybrid. - `"vector"` - `"fts"` - `"hybrid"` - `tags: optional array of string` Filter by tags (match any). - `tool_types: optional array of string` Filter by tool types (e.g., 'custom', 'letta_core'). ### Returns - `combined_score: number` Combined relevance score (RRF for hybrid mode). - `tool: Tool` The matched tool. - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` - `embedded_text: optional string` The embedded text content used for matching. - `fts_rank: optional number` Full-text search rank position. - `vector_rank: optional number` Vector search rank position. ### Example ```http curl https://api.letta.com/v1/tools/search \ -H 'Content-Type: application/json' \ -H "Authorization: Bearer $LETTA_API_KEY" \ -d '{}' ``` #### Response ```json [ { "combined_score": 0, "tool": { "id": "tool-123e4567-e89b-12d3-a456-426614174000", "args_json_schema": { "foo": "bar" }, "created_by_id": "created_by_id", "default_requires_approval": true, "description": "description", "enable_parallel_execution": true, "json_schema": { "foo": "bar" }, "last_updated_by_id": "last_updated_by_id", "metadata_": { "foo": "bar" }, "name": "name", "npm_requirements": [ { "name": "x", "version": "version" } ], "pip_requirements": [ { "name": "x", "version": "version" } ], "project_id": "project_id", "return_char_limit": 1, "source_code": "source_code", "source_type": "source_type", "tags": [ "string" ], "tool_type": "custom" }, "embedded_text": "embedded_text", "fts_rank": 0, "vector_rank": 0 } ] ``` ## Domain Types ### Npm Requirement - `NpmRequirement object { name, version }` - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. ### Pip Requirement - `PipRequirement object { name, version }` - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. ### Tool - `Tool object { id, args_json_schema, created_by_id, 15 more }` Representation of a tool, which is a function that can be called by the agent. - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` ### Tool Create - `ToolCreate object { source_code, args_json_schema, default_requires_approval, 8 more }` - `source_code: string` The source code of the function. - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `default_requires_approval: optional boolean` Whether or not to require approval before executing this tool. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function (auto-generated from source_code if not provided) - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_type: optional string` The source type of the function. - `tags: optional array of string` Metadata tags. ### Tool Return Message - `ToolReturnMessage object { id, date, status, 13 more }` A message representing the return value of a tool call (generated by Letta executing the requested tool). Args: id (str): The ID of the message date (datetime): The date the message was created in ISO format name (Optional[str]): The name of the sender of the message tool_return (str): The return value of the tool (deprecated, use tool_returns) status (Literal["success", "error"]): The status of the tool call (deprecated, use tool_returns) tool_call_id (str): A unique identifier for the tool call that generated this message (deprecated, use tool_returns) stdout (Optional[List(str)]): Captured stdout (e.g. prints, logs) from the tool invocation (deprecated, use tool_returns) stderr (Optional[List(str)]): Captured stderr from the tool invocation (deprecated, use tool_returns) tool_returns (Optional[List[ToolReturn]]): List of tool returns for multi-tool support - `id: string` - `date: string` - `status: "success" or "error"` - `"success"` - `"error"` - `tool_call_id: string` - `tool_return: string` - `is_err: optional boolean` - `message_type: optional "tool_return_message"` The type of the message. - `"tool_return_message"` - `name: optional string` - `otid: optional string` The offline threading id (OTID). Set by the client to deduplicate requests. Used for idempotency in background streaming mode — each message in a request must have a unique OTID. Retries of the same request should reuse the same OTIDs. - `run_id: optional string` - `sender_id: optional string` - `seq_id: optional number` - `stderr: optional array of string` - `stdout: optional array of string` - `step_id: optional string` - `tool_returns: optional array of ToolReturn` - `status: "success" or "error"` - `"success"` - `"error"` - `tool_call_id: string` - `tool_return: array of TextContent or ImageContent or string` The tool return value - either a string or list of content parts (text/image) - `array of TextContent or ImageContent` - `TextContent object { text, signature, type }` - `text: string` The text content of the message. - `signature: optional string` Stores a unique identifier for any reasoning associated with this text content. - `type: optional "text"` The type of the message. - `"text"` - `ImageContent object { source, type }` - `source: object { url, type } or object { data, media_type, detail, type } or object { file_id, data, detail, 2 more }` The source of the image. - `URL object { url, type }` - `url: string` The URL of the image. - `type: optional "url"` The source type for the image. - `"url"` - `Base64 object { data, media_type, detail, type }` - `data: string` The base64 encoded image data. - `media_type: string` The media type for the image. - `detail: optional string` What level of detail to use when processing and understanding the image (low, high, or auto to let the model decide) - `type: optional "base64"` The source type for the image. - `"base64"` - `Letta object { file_id, data, detail, 2 more }` - `file_id: string` The unique identifier of the image file persisted in storage. - `data: optional string` The base64 encoded image data. - `detail: optional string` What level of detail to use when processing and understanding the image (low, high, or auto to let the model decide) - `media_type: optional string` The media type for the image. - `type: optional "letta"` The source type for the image. - `"letta"` - `type: optional "image"` The type of the message. - `"image"` - `string` - `stderr: optional array of string` - `stdout: optional array of string` - `type: optional "tool"` The message type to be created. - `"tool"` ### Tool Search Request - `ToolSearchRequest object { limit, query, search_mode, 2 more }` Request model for searching tools using semantic search. - `limit: optional number` Maximum number of results to return. - `query: optional string` Text query for semantic search. - `search_mode: optional "vector" or "fts" or "hybrid"` Search mode: vector, fts, or hybrid. - `"vector"` - `"fts"` - `"hybrid"` - `tags: optional array of string` Filter by tags (match any). - `tool_types: optional array of string` Filter by tool types (e.g., 'custom', 'letta_core'). ### Tool Search Result - `ToolSearchResult object { combined_score, tool, embedded_text, 2 more }` Result from a tool search operation. - `combined_score: number` Combined relevance score (RRF for hybrid mode). - `tool: Tool` The matched tool. - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` - `embedded_text: optional string` The embedded text content used for matching. - `fts_rank: optional number` Full-text search rank position. - `vector_rank: optional number` Vector search rank position. ### Tool Type - `ToolType = "custom" or "letta_core" or "letta_memory_core" or 8 more` - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` ### Tool Delete Response - `ToolDeleteResponse = unknown` ### Tool Search Response - `ToolSearchResponse = array of ToolSearchResult` - `combined_score: number` Combined relevance score (RRF for hybrid mode). - `tool: Tool` The matched tool. - `id: string` The human-friendly ID of the Tool - `args_json_schema: optional map[unknown]` The args JSON schema of the function. - `created_by_id: optional string` The id of the user that made this Tool. - `default_requires_approval: optional boolean` Default value for whether or not executing this tool requires approval. - `description: optional string` The description of the tool. - `enable_parallel_execution: optional boolean` If set to True, then this tool will potentially be executed concurrently with other tools. Default False. - `json_schema: optional map[unknown]` The JSON schema of the function. - `last_updated_by_id: optional string` The id of the user that made this Tool. - `metadata_: optional map[unknown]` A dictionary of additional metadata for the tool. - `name: optional string` The name of the function. - `npm_requirements: optional array of NpmRequirement` Optional list of npm packages required by this tool. - `name: string` Name of the npm package. - `version: optional string` Optional version of the package, following semantic versioning. - `pip_requirements: optional array of PipRequirement` Optional list of pip packages required by this tool. - `name: string` Name of the pip package. - `version: optional string` Optional version of the package, following semantic versioning. - `project_id: optional string` The project id of the tool. - `return_char_limit: optional number` The maximum number of characters in the response. - `source_code: optional string` The source code of the function. - `source_type: optional string` The type of the source code. - `tags: optional array of string` Metadata tags. - `tool_type: optional ToolType` The type of the tool. - `"custom"` - `"letta_core"` - `"letta_memory_core"` - `"letta_multi_agent_core"` - `"letta_sleeptime_core"` - `"letta_voice_sleeptime_core"` - `"letta_builtin"` - `"letta_files_core"` - `"external_langchain"` - `"external_composio"` - `"external_mcp"` - `embedded_text: optional string` The embedded text content used for matching. - `fts_rank: optional number` Full-text search rank position. - `vector_rank: optional number` Vector search rank position.