Optional mapping of message types to their allowed content blocks. Each message type can specify what content block types it supports (text, images, etc).
Optional
Readonly
outputOptional output version for the message structure. If not provided, defaults to "v0".
Optional mapping of message types to arbitrary property objects. Allows attaching custom metadata or other information to specific message types.
Properties specific to AI messages
Metadata about the AI model response
Usage statistics for the AI response
Metadata about the human message
Metadata about the system message
Metadata about the tool message
Optional
Readonly
toolsOptional set of tool definitions that can be used in messages. Each tool is defined with input/output types and can be referenced in tool messages.
Standard message structured used to define the most basic message structure that's used throughout the library.
This is also the message structure that's used when a message structure is not provided.