Struct Message 

pub struct Message {
    pub role: Role,
    pub parts: Vec<MessagePart>,
    pub message_id: Option<String>,
    pub task_id: Option<String>,
    pub context_id: Option<String>,
    pub metadata: Option<HashMap<String, Value>>,
    pub extensions: Option<HashMap<String, Value>>,
}

A message in the A2A protocol

Messages are the primary unit of communication between agents. Each message has a role (user or assistant), one or more parts (text, file, or data), and optional metadata and extensions.

Fields

role: Role

Role of the message sender

parts: Vec<MessagePart>

Message content parts (at least one required)

message_id: Option<String>

Optional message identifier

task_id: Option<String>

Optional task identifier (for associating message with a task)

context_id: Option<String>

Optional context identifier (for multi-turn conversations)

metadata: Option<HashMap<String, Value>>

Optional metadata for the message

extensions: Option<HashMap<String, Value>>

Optional extensions indicating additional protocol features

Implementations

impl Message

pub fn new(role: Role, text: impl Into<String>) -> Self

Create a new message with text content

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

Create a user message with text content

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

Create an assistant message with text content

pub fn builder() -> MessageBuilder

Create a new message builder

pub fn with_metadata(self, key: impl Into<String>, value: Value) -> Self

Add a metadata field to the message

pub fn with_extension(self, key: impl Into<String>, value: Value) -> Self

Add an extension to the message

pub fn with_part(self, part: MessagePart) -> Self

Add a message part

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 PartialEq for Message

fn eq(&self, other: &Message) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

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.

impl StructuralPartialEq for Message