Add typed event emitter to BaseConversation

[kraenhansen]

Summary

• Add on(), off(), and emit() methods to BaseConversation with full ConversationEventMap typing
• on() returns an unsubscribe function; multiple listeners per event are supported
• Constructor-provided callbacks are automatically registered as initial listeners via CALLBACK_KEY_TO_EVENT_NAME
• Replace all this.options.onXxx() invocations in BaseConversation with this.emit() calls
• Add changeset for @elevenlabs/client minor bump

Part of #738 (PR 4/6).

Test plan

• All 97 client tests pass (including agent_response_correction callback test)
• All 30 turbo tasks pass (build, check-types, lint across all packages)
• Existing Conversation.startSession({ onMessage: ... }) API unchanged
• Manual: verify events fire correctly in agent-testbench example

🤖 Generated with Claude Code

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Note

Medium Risk
Refactors how conversation events are dispatched (callbacks now routed through an emitter), which could subtly change event ordering/duplication and error propagation across the SDK.

Overview
Adds a typed event emitter API to conversations via new BaseConversation.on()/off() (with on() returning an unsubscribe) and an internal emit().

Re-routes all existing constructor callback options (onMessage, onDisconnect, etc.) through the emitter by auto-registering them at construction time and replacing direct options.onXxx() calls with emit() invocations (including guarded handling for unhandled-client-tool-call).

Includes a @elevenlabs/client changeset for a minor version bump and updates the BaseConversation test harness to call the renamed message handler.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Listener errors silently swallowed, bypassing console.error

Medium Severity

When a non-error listener throws, the emit catch block calls this.emit("error", String(error)) instead of this.onError(...). This bypasses the console.error call in the private onError method. Since getFullOptions registers a default no-op onError: () => {} as a listener, listener errors are completely silenced when no custom error handler is provided. Calling this.onError(String(error)) instead would preserve console visibility while still being safe from infinite recursion (the existing event !== "error" guard in the catch block would prevent it).

Additional Locations (1)

• packages/client/src/BaseConversation.ts#L543-L547

 

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