Struct RunStartContext 

pub struct RunStartContext {
    pub session_id: Uuid,
    pub model: String,
    pub working_directory: String,
}

Context provided to on_run_start hooks.

Fires at the start of each run() call, before any turns run. Carries the session identifier, the model that will handle the first request, and the working directory the agent treats as its root. Notification-only — use it to initialize per-run state (open resources, set up tracking, log the start).

Fields

session_id: Uuid

Session ID.

Unique identifier for the agent session that owns this run, letting hooks initialize any per-session state they track.

model: String

Model identifier.

The model the session will use for its first request (e.g. a provider name like "claude-3-opus"). May change later if fallback or an explicit model switch occurs.

working_directory: String

Working directory the agent was started in.

The filesystem path the agent treats as its root for relative tool calls, useful for hooks that log or restrict operations by location.

Trait Implementations

impl Clone for RunStartContext

fn clone(&self) -> RunStartContext

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RunStartContext

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

Formats the value using the given formatter.