Message

The basic data structure in AgentScope

Message (Msg) is the basic data structure in AgentScope, responsible for exchanging information among agents, users, and tools.

Its basic fields include:

Field	Description
id	Unique identifier for the message
name	The name of the message sender
role	The role of the message sender (“user”, “assistant”, “system”)
content	The content of the message, which can be text, image, video, audio, tool calls, tool results, etc.
timestamp	The time when the message was created
metadata	Additional information about the message, such as tool calls, reasoning traces, etc.

The content field can be a plain string for simple text messages, or a list of content blocks for multimodal and tool call messages. Each content block is a dictionary with a type field indicating the content type.

Supported content block types:

Type	Example
text	{"type": "text", "text": "Hello AgentScope!"}
thinking	{"type": "thinking", "thinking": "Hmm, let me think..."}
image	{"type": "image", "source": {"type": "url", "url": "https://xxx/image.jpg"}}
video	{"type": "video", "source": {"type": "url", "url": "https://xxx/video.mp4"}}
audio	{"type": "audio", "source": {"type": "url", "url": "https://xxx/audio.mp3"}}
tool_use	{"type": "tool_use", "id": "xxxx", "name": "search", "input": {"query": "..."}}
tool_result	{"type": "tool_result", "id": "xxxx", "name": "search", "output": "..."}

Quick examples:

from agentscope.message import Msg

# A simple text message
msg = Msg(name="Friday", content="Hello, I'm your assistant!", role="assistant")

# Multimodal message
msg = Msg(
    name="Bob",
    content=[
        {"type": "text", "text": "How about this image?"},
        {"type": "image", "source": {"type": "url", "url": "https://example.com/image.jpg"}},
    ],
    role="user",
)

# Tool call message
msg = Msg(
    name="Alice",
    content=[
        {
            "type": "tool_use",
            "id": "xxxx",
            "name": "search",
            "input": {"query": "What's the weather today?"}
        }
    ],
    role="user",
)