Letta · Schema

ToolReturn

Artificial IntelligenceAgentsStateful AgentsMemoryMemGPTContinual LearningMCPMulti-AgentRAGOpen-Source

Properties

Name	Type	Description
tool_call_id	object	The ID for the tool call
status	string	The status of the tool call
stdout	object	Captured stdout (e.g. prints, logs) from the tool invocation
stderr	object	Captured stderr from the tool invocation
func_response	object	The function response - either a string or list of content parts (text/image)

View JSON Schema on GitHub

JSON Schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "#/components/schemas/letta__schemas__message__ToolReturn-Output",
  "title": "ToolReturn",
  "properties": {
    "tool_call_id": {
      "anyOf": [
        {},
        {
          "type": "null"
        }
      ],
      "title": "Tool Call Id",
      "description": "The ID for the tool call"
    },
    "status": {
      "type": "string",
      "enum": [
        "success",
        "error"
      ],
      "title": "Status",
      "description": "The status of the tool call"
    },
    "stdout": {
      "anyOf": [
        {
          "items": {
            "type": "string"
          },
          "type": "array"
        },
        {
          "type": "null"
        }
      ],
      "title": "Stdout",
      "description": "Captured stdout (e.g. prints, logs) from the tool invocation"
    },
    "stderr": {
      "anyOf": [
        {
          "items": {
            "type": "string"
          },
          "type": "array"
        },
        {
          "type": "null"
        }
      ],
      "title": "Stderr",
      "description": "Captured stderr from the tool invocation"
    },
    "func_response": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "items": {
            "oneOf": [
              {
                "$ref": "#/components/schemas/TextContent"
              },
              {
                "$ref": "#/components/schemas/ImageContent"
              }
            ],
            "discriminator": {
              "propertyName": "type",
              "mapping": {
                "image": "#/components/schemas/ImageContent",
                "text": "#/components/schemas/TextContent"
              }
            }
          },
          "type": "array"
        },
        {
          "type": "null"
        }
      ],
      "title": "Func Response",
      "description": "The function response - either a string or list of content parts (text/image)"
    }
  },
  "type": "object",
  "required": [
    "status"
  ]
}

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