Struct Message 

pub struct Message {
    pub id: Option<String>,
    pub role: Role,
    pub content: String,
    pub tool_calls: Option<Vec<ToolCall>>,
    pub tool_call_id: Option<String>,
    pub visibility: Visibility,
    pub metadata: Option<MessageMetadata>,
}

A message in the conversation.

Fields

id: Option<String>

Stable message identifier (UUID v7, auto-generated).

role: Role

content: String

tool_calls: Option<Vec<ToolCall>>

Tool calls made by the assistant.

tool_call_id: Option<String>

Tool call ID this message responds to (for tool role).

visibility: Visibility

Message visibility. Defaults to All (visible everywhere). Internal messages (e.g. system reminders) are only sent to the LLM.

metadata: Option<MessageMetadata>

Optional run/step association metadata.

Implementations

impl Message

pub fn system(content: impl Into<String>) -> Self

Create a system message.

pub fn internal_system(content: impl Into<String>) -> Self

Create an internal system message (visible only to LLM, hidden from API consumers).

Use this for plugin-injected reminders, system hints, and other messages that should be part of the LLM context but not exposed to end users.

pub fn user(content: impl Into<String>) -> Self

Create a user message.

pub fn assistant(content: impl Into<String>) -> Self

Create an assistant message.

pub fn assistant_with_tool_calls( content: impl Into<String>, calls: Vec<ToolCall>, ) -> Self

Create an assistant message with tool calls.

pub fn tool(call_id: impl Into<String>, content: impl Into<String>) -> Self

Create a tool response message.

pub fn with_id(self, id: String) -> Self

Override the auto-generated message ID.

pub fn with_metadata(self, metadata: MessageMetadata) -> Self

Attach run/step metadata to this message.

Trait Implementations

impl Clone for Message

fn clone(&self) -> Message

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Message

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Message

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for Message

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.