May 19, 2025

Speech to text logprobs: The Speech to Text response now includes a logprob field for word prediction confidence.

Improved API error messages: Enhanced API error messages for subscriptions with failed payments. This provides clearer information if a failed payment has caused a user to reach their quota threshold sooner than expected.

Batch calls: Released new batch calling functionality, which allows you to automate groups of outbound calls.
Increased evaluation criteria limit: The maximum number of evaluation criteria for agent performance evaluation has been increased from 5 to 10.
Human-readable IDs: Introduced human-readable IDs for key Agents Platform entities (e.g., agents, conversations). This improves usability and makes resources easier to identify and manage through the API and UI.
Unanswered call tracking: 'Not Answered' outbound calls are now reliably detected and visible in the conversation history.
LLM cost visibility in dashboard: The Agents Platform dashboard now displays the total and per-minute average LLM costs.
Zero retention mode (ZRM) for agents: Allowed enabling Zero Retention Mode (ZRM) per agent.
Dynamic variables in headers: Added option of setting dynamic variable as a header value for tools
Customisable tool timeouts: Shipped setting different timeout durations per tool.

Simplified secret updates: Workspace secrets can now be updated more granularly using a PATCH request via the API, simplifying the management of individual secret values. For technical details, please see the API changes section below.

View API changes

New Endpoints

Agents & Conversations:
- Endpoint GET /v1/convai/conversation/get_signed_url (snake_case path) has been deprecated. Use the new GET /v1/convai/conversation/get-signed-url (kebab-case path) instead.
Phone Numbers:
- Get Phone Number Details - Response schema for GET /v1/convai/phone-numbers/{phone_number_id} updated to distinct Twilio and SIPTrunk provider details.
- Update Phone Number - Response schema for PATCH /v1/convai/phone-numbers/{phone_number_id} updated similarly for Twilio and SIPTrunk.
- List Phone Numbers - Response schema for GET /v1/convai/phone-numbers/ list items updated for Twilio and SIPTrunk providers.

Text to Speech Endpoints - Default model_id changed from eleven_monolingual_v1 to eleven_multilingual_v2 for the following endpoints:
- POST /v1/text-to-speech/{voice_id}/stream
- POST /v1/text-to-speech/{voice_id}/stream-with-timestamps
- POST /v1/text-to-speech/{voice_id}
- POST /v1/text-to-speech/{voice_id}/with-timestamps

Get Shared Voices - Added include_custom_rates query parameter to GET /v1/shared-voices.
Schema Updates:
- LibraryVoiceResponseModel and VoiceSharingResponseModel now include an optional fiat_rate field (USD per 1000 credits).