Enum MessageRole 

pub enum MessageRole {
    System,
    User,
    Assistant,
    Tool,
}

Variants

System

User

Assistant

Tool

Implementations

impl MessageRole

pub fn as_gemini_str(&self) -> &'static str

Get the role string for Gemini API Note: Gemini API has specific constraints on message roles

• Only accepts “user” and “model” roles in conversations
• System messages are handled separately as system instructions
• Tool responses are sent as “user” role with function response format

pub fn as_openai_str(&self) -> &'static str

Get the role string for OpenAI API OpenAI supports all standard role types including:

• system, user, assistant, tool
• function (legacy, now replaced by tool)

pub fn as_anthropic_str(&self) -> &'static str

Get the role string for Anthropic API Anthropic has specific handling for tool messages:

• Supports user, assistant roles normally
• Tool responses are treated as user messages
• System messages can be handled as system parameter or hoisted

pub fn as_generic_str(&self) -> &'static str

Get the role string for generic OpenAI-compatible providers Most providers follow OpenAI’s role conventions

pub fn can_make_tool_calls(&self) -> bool

Check if this role supports tool calls Only Assistant role can initiate tool calls in most APIs

pub fn is_tool_response(&self) -> bool

Check if this role represents a tool response

pub fn validate_for_provider( &self, provider: &str, has_tool_call_id: bool, ) -> Result<(), String>

Validate message role constraints for a given provider Based on official API documentation requirements

Trait Implementations

impl Clone for MessageRole

fn clone(&self) -> MessageRole

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for MessageRole

impl Debug for MessageRole

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

Formats the value using the given formatter.

impl Default for MessageRole

fn default() -> MessageRole

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for MessageRole

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for MessageRole

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

Formats the value using the given formatter.

impl Eq for MessageRole

impl PartialEq for MessageRole

fn eq(&self, other: &MessageRole) -> 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 MessageRole

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 MessageRole