Struct Message 

pub struct Message {
    pub native_tool_calls: Vec<NativeToolCall>,
    pub role: MessageRole,
    pub content: MessageContent,
    pub tool_calls: Option<Vec<ToolCall>>,
    pub tool_call_id: Option<String>,
    pub phase: Option<ExecutionPhase>,
    pub reasoning: Vec<ReasoningContentPart>,
    pub configuration_update: Option<ReasoningEffort>,
}

Message format for LLM calls (provider-agnostic): the request-shaped view a driver turns into provider wire format. Distinct from the lossless stored runtime message, which the runtime conversion layer maps here.

Fields

native_tool_calls: Vec<NativeToolCall>

Provider-native call identities, retained alongside portable fallbacks.

role: MessageRole

content: MessageContent

tool_calls: Option<Vec<ToolCall>>

tool_call_id: Option<String>

phase: Option<ExecutionPhase>

Execution phase for assistant messages. Helps models distinguish between intermediate working commentary (Commentary) and completed answers (FinalAnswer) in multi-step tool-calling flows. Only set on assistant messages. Must be preserved when replaying conversation history.

reasoning: Vec<ReasoningContentPart>

Provider reasoning artifacts for this assistant turn, in emission order.

Drivers replay these verbatim in the position the provider issued them: each keeps its own signature, id and encrypted payload, so interleaved thinking and per-call thought signatures survive a round trip. Empty for messages without reasoning.

configuration_update: Option<ReasoningEffort>

Astra effort transition immediately before this message. Other protocols ignore it; it is never rendered as conversation text.

Implementations

impl Message

pub fn text(role: MessageRole, content: impl Into<String>) -> Self

Create a message with text content

pub fn parts(role: MessageRole, parts: Vec<LlmContentPart>) -> Self

Create a message with content parts (text, images, audio)

pub fn content_as_text(&self) -> String

Get content as plain text string (for simple cases)

pub fn prepend_text_prefix(&mut self, prefix: &str)

Prepend a prefix to the first text content.

Used by ReasonAtom to inject external actor identity (e.g. "[Alice] ") into user messages from external channels.

pub fn mark_turn_scoped_system(&mut self)

Mark this system message as scoped to the current model turn.

Trait Implementations

impl Clone for Message

fn clone(&self) -> Self

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.