Enum ChatMessage 

pub enum ChatMessage {
    System {
        content: String,
        ephemeral: bool,
    },
    User {
        content: String,
        images: Vec<ImageAttachment>,
        ephemeral: bool,
    },
    Assistant {
        content: Option<String>,
        reasoning_content: Option<String>,
        thinking_signature: Option<String>,
        tool_calls: Option<Vec<ToolCallMessage>>,
    },
    Tool {
        tool_call_id: String,
        name: Option<String>,
        content: String,
    },
    Custom {
        role: String,
        data: Value,
    },
}

A chat message in a conversation.

Supports system, user, assistant, tool, and custom message types. Each variant carries the data needed for LLM API calls.

Variants

System

Fields

content: String

ephemeral: bool

Ephemeral messages are cleaned up after each turn and skipped during persistence.

User

Fields

content: String

images: Vec<ImageAttachment>

ephemeral: bool

Ephemeral messages are cleaned up after each turn and skipped during persistence.

Assistant

Fields

content: Option<String>

reasoning_content: Option<String>

thinking_signature: Option<String>

Anthropic requires thinking blocks with signature to be sent back in multi-turn conversations. This field stores the signature.

tool_calls: Option<Vec<ToolCallMessage>>

Tool

Fields

tool_call_id: String

name: Option<String>

content: String

Custom

Application-defined message type for extensibility.

Custom messages are preserved in the transcript but filtered out by the default conversion before being sent to the LLM provider.

Fields

role: String

data: Value

Implementations

impl ChatMessage

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

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

Create an ephemeral system message: auto-cleaned after turn, not persisted.

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

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

Create an ephemeral user message: auto-cleaned after turn, not persisted.

pub fn user_with_images( content: impl Into<String>, images: Vec<ImageAttachment>, ) -> Self

pub fn is_ephemeral(&self) -> bool

Whether this is an ephemeral message (auto-cleaned after turn, not persisted).

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

pub fn assistant_with_reasoning( content: impl Into<String>, reasoning: impl Into<String>, ) -> Self

pub fn assistant_tool_call( tool_call_id: impl Into<String>, tool_name: impl Into<String>, arguments: impl Into<String>, ) -> Self

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

pub fn tool_with_name( tool_call_id: impl Into<String>, name: impl Into<String>, content: impl Into<String>, ) -> Self

Trait Implementations

impl Clone for ChatMessage

fn clone(&self) -> ChatMessage

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ChatMessage

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ChatMessage

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for ChatMessage

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

where __S: Serializer,

Serialize this value into the given Serde serializer.