Deprecating on 06/15/2026

Legacy list endpoints are deprecated

The following list endpoints are deprecated in favor of newer versioned endpoints with unified pagination patterns.

Affected APIs:

• List Batch Tests
• List Conversation Flow Components
• List Conversation Flows
• List Phone Numbers
• List Retell LLMs
• List Test Case Definitions
• List Test Runs
• List Calls
• List Chats

Endpoint migrations

• GET /list-batch-tests -> GET /v2/list-batch-tests (List Batch Tests)
• GET /list-conversation-flow-components -> GET /v2/list-conversation-flow-components (List Conversation Flow Components)
• GET /list-conversation-flows -> GET /v2/list-conversation-flows (List Conversation Flows)
• GET /list-phone-numbers -> GET /v2/list-phone-numbers (List Phone Numbers)
• GET /list-retell-llms -> GET /v2/list-retell-llms (List Retell LLMs)
• GET /list-test-case-definitions -> GET /v2/list-test-case-definitions (List Test Case Definitions)
• GET /list-test-runs/{test_case_batch_job_id} -> GET /v2/list-test-runs/{test_case_batch_job_id} (List Test Runs)
• POST /v2/list-calls -> POST /v3/list-calls (List Calls)
• GET /list-chat -> POST /v3/list-chats (List Chats)

What’s changing on 06/15/2026:

1. The legacy list endpoints above will no longer be supported.
2. GET /list-chat changes both method and path to POST /v3/list-chats.
3. Versioned list endpoints return unified pagination fields: items, pagination_key, and has_more.

Migration:

• Update each client call to the new method/path listed above.
• Update response handling to read items from the paginated response object (instead of expecting a top-level array from legacy endpoints).
• Keep using pagination_key and has_more for page traversal.

Effective date: After 06/15/2026, the legacy endpoints listed above will no longer be supported.

Analysis prompt fields are deprecated

The following top-level analysis prompt fields on voice and chat agent configurations are deprecated in favor of the post_call_analysis_data and post_chat_analysis_data arrays.

Deprecated fields:

• analysis_summary_prompt
• analysis_successful_prompt
• analysis_user_sentiment_prompt

These fields exist on both voice agent and chat agent endpoints:

• Create Agent / Update Agent
• Create Chat Agent / Update Chat Agent

What’s changing on 06/15/2026:

1. The three prompt fields above will be removed from the API.
2. Use system preset items inside post_call_analysis_data (voice agents) or post_chat_analysis_data (chat agents) to customize prompts for summary, success, and sentiment analysis.

Migration:

Replace each deprecated field with a system preset entry in the corresponding analysis data array. Set type to system-presets, name to the preset identifier, and description to your custom prompt.

Deprecated field	Preset name (voice)	Preset name (chat)
analysis_summary_prompt	call_summary	chat_summary
analysis_successful_prompt	call_successful	chat_successful
analysis_user_sentiment_prompt	user_sentiment	user_sentiment

For example, if you currently set analysis_summary_prompt on a voice agent:

Before

{
  "analysis_summary_prompt": "Summarize the outcome of the conversation in two sentences."
}