Struct AgUiEventContext 

pub struct AgUiEventContext {
    pub message_id: String,
    /* private fields */
}

Context for AG-UI event conversion.

Maintains state needed for converting internal AgentEvents to AG-UI events. State is initialized from the first RunStart event in the stream.

Fields

message_id: String

Current message identifier.

Implementations

impl AgUiEventContext

pub fn new() -> Self

Create a new AG-UI context.

The context is fully initialized when the first RunStart event arrives, which generates an independent message_id (UUID v7).

pub fn with_frontend_run_id(self, run_id: impl Into<String>) -> Self

Set a frontend run id used in outward-facing AG-UI lifecycle events.

pub fn next_step_name(&mut self) -> String

Generate the next step name.

pub fn current_step_name(&self) -> String

Get the current step name.

pub fn start_text(&mut self) -> bool

Mark text stream as started.

If text was previously ended, a new message_id is generated so that each TEXT_MESSAGE_START / TEXT_MESSAGE_END cycle uses a unique ID. This prevents CopilotKit / AG-UI runtimes from confusing reopened message IDs with already-ended ones (which causes “text-end for missing text part” errors on the frontend).

pub fn end_text(&mut self) -> bool

Mark text stream as ended and return whether it was active.

pub fn is_text_open(&self) -> bool

Whether a text stream is currently open.

pub fn start_reasoning(&mut self) -> bool

Mark reasoning stream as started.

pub fn end_reasoning(&mut self) -> bool

Mark reasoning stream as ended and return whether it was active.

pub fn reset_for_step(&mut self, message_id: String)

Reset text lifecycle state for a new step with a pre-generated message ID.

This ensures that the streaming message ID matches the stored Message.id for the assistant message produced by this step.

pub fn new_message_id(&mut self) -> String

Generate a new message ID.

pub fn on_agent_event(&mut self, ev: &AgentEvent) -> Vec<Event>

Convert an AgentEvent to AG-UI protocol compatible events.

Handles full stream lifecycle: text start/end pairs, step counters, terminal event suppression (after Error), and Pending event filtering.

Trait Implementations

impl Clone for AgUiEventContext

fn clone(&self) -> AgUiEventContext

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AgUiEventContext

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

Formats the value using the given formatter.

impl Default for AgUiEventContext

fn default() -> Self

Returns the “default value” for a type.