Struct EventBridge 

pub struct EventBridge { /* private fields */ }

Bridge between agent code and AG-UI protocol events.

This is the main interface for emitting events from agent code. It handles the AG-UI protocol details like run IDs, message IDs, and event sequencing.

Implementations

impl EventBridge

pub fn new( event_tx: Sender<Event<JsonValue>>, thread_id: Arc<RwLock<ThreadId>>, run_id: Arc<RwLock<Option<RunId>>>, ) -> Self

Creates a new event bridge.

pub async fn start_run(&self)

Starts a new agent run.

Call this at the beginning of an agent interaction.

pub async fn finish_run(&self)

Finishes the current run successfully.

pub async fn finish_run_with_error(&self, message: &str)

Finishes the current run with an error.

pub async fn interrupt(&self, reason: Option<&str>, payload: Option<Value>)

Interrupt the current run for human-in-the-loop interaction.

This emits a RunFinished event with outcome: Interrupt, signaling that the frontend should show approval UI and resume with user input.

Arguments

• reason - Optional interrupt reason (e.g., “file_write”, “deployment”)
• payload - Optional JSON payload with context for the approval UI

pub async fn interrupt_with_id( &self, id: &str, reason: Option<&str>, payload: Option<Value>, )

Interrupt with a tracking ID for correlation.

The interrupt ID can be used by the client to correlate the resume request with the original interrupt.

pub async fn start_message(&self) -> MessageId

Starts a new text message from the assistant.

pub async fn emit_text_chunk(&self, delta: &str)

Emits a text chunk as part of the current message.

pub async fn end_message(&self)

Ends the current text message.

pub async fn emit_message(&self, content: &str)

Convenience: Emits a complete text message (start + content + end).

pub async fn start_tool_call(&self, name: &str, args: &JsonValue) -> ToolCallId

Starts a tool call.

Returns the tool call ID for use with subsequent events.

pub async fn emit_tool_args_chunk(&self, tool_call_id: &ToolCallId, delta: &str)

Emits a chunk of tool call arguments (for streaming args).

pub async fn end_tool_call(&self, tool_call_id: &ToolCallId)

Ends a tool call.

Note: Tool results are handled separately via messages in AG-UI protocol.

pub async fn emit_tool_call(&self, name: &str, args: &JsonValue)

Convenience: Emits a complete tool call (start + end).

pub async fn emit_state_snapshot(&self, state: JsonValue)

Emits a state snapshot.

pub async fn emit_state_delta(&self, delta: Vec<JsonValue>)

Emits a state delta (JSON Patch).

pub async fn start_thinking(&self, title: Option<&str>)

Starts a thinking/processing step.

pub async fn end_thinking(&self)

Ends the current thinking step.

pub async fn start_step(&self, name: &str)

Starts a step in the agent workflow.

pub async fn end_step(&self)

Ends the current step.

pub async fn emit_custom(&self, name: &str, value: JsonValue)

Emits a custom event.

Trait Implementations

impl Clone for EventBridge

fn clone(&self) -> EventBridge

Returns a duplicate of the value.

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

Performs copy-assignment from source.