---
title: "Changes to POST /create-retell-llm"
method: POST
path: "/create-retell-llm"
---

# Changes to POST /create-retell-llm

`POST /create-retell-llm`

> Every recorded change to this endpoint, newest first.

## Timeline

Changed in 14 of 28 revisions.

- **2026-05-28** `40402ca870b9` — 4 warning, 8 info
- **2026-05-18** `6342a9990108` — 2 warning
- **2026-05-11** `7c30e3ea2536` — 1 warning, 1 info
- **2026-05-08** `7dd16ddf69d8` — 4 breaking, 2 warning, 2 info
- **2026-05-07** `f1a0d7c1e36c` — 5 breaking, 1 info
- **2026-04-28** `1b4a9d84942a` — 2 breaking, 1 warning, 3 info
- **2026-04-20** `8ee53928bf31` — 2 breaking, 1 warning, 15 info
- **2026-04-01** `56de19127afb` — 28 info
- **2026-03-19** `3aa6f6e028ef` — 2 breaking, 2 warning, 8 info
- **2026-03-17** `424df3aa7900` — 2 breaking, 6 warning, 28 info
- **2026-03-09** `8fbf8c54a142` — 12 breaking, 1 warning, 29 info
- **2026-02-10** `0bf5cea5dfcc` — 4 info
- **2026-02-06** `dfad228ab4a4` — 8 breaking, 28 info
- **2026-01-23** `427e77039f39` — 4 info

## Changes

- **2026-05-28** `40402ca870b9` — 4 warning, 8 info
  - changed the pattern of the request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version/oneOf[subschema #2]/` from `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` to `^(latest|latest_published|(?!(?:latest|latest_published|v\d+)$)[a-z][a-z0-9_-]{0,19})$`
  - changed the pattern of the request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_version/oneOf[subschema #2]/` from `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` to `^(latest|latest_published|(?!(?:latest|latest_published|v\d+)$)[a-z][a-z0-9_-]{0,19})$`
  - changed the pattern of the request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version/oneOf[subschema #2]/` from `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` to `^(latest|latest_published|(?!(?:latest|latest_published|v\d+)$)[a-z][a-z0-9_-]{0,19})$`
  - changed the pattern of the request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_version/oneOf[subschema #2]/` from `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` to `^(latest|latest_published|(?!(?:latest|latest_published|v\d+)$)[a-z][a-z0-9_-]{0,19})$`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/enable_typing_sound`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/enable_typing_sound`
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/enable_typing_sound` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/enable_typing_sound` to the response with the `201` status
  - the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version/oneOf[subschema #2]/` response's property pattern was changed from `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` to `^(latest|latest_published|(?!(?:latest|latest_published|v\d+)$)[a-z][a-z0-9_-]{0,19})$` for the status `201`
  - the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_version/oneOf[subschema #2]/` response's property pattern was changed from `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` to `^(latest|latest_published|(?!(?:latest|latest_published|v\d+)$)[a-z][a-z0-9_-]{0,19})$` for the status `201`
  - the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version/oneOf[subschema #2]/` response's property pattern was changed from `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` to `^(latest|latest_published|(?!(?:latest|latest_published|v\d+)$)[a-z][a-z0-9_-]{0,19})$` for the status `201`
  - the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_version/oneOf[subschema #2]/` response's property pattern was changed from `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` to `^(latest|latest_published|(?!(?:latest|latest_published|v\d+)$)[a-z][a-z0-9_-]{0,19})$` for the status `201`
- **2026-05-18** `6342a9990108` — 2 warning
  - removed the request property `allOf[subschema #2]/version`
  - removed the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/version` from the response with the `201` status
- **2026-05-11** `7c30e3ea2536` — 1 warning, 1 info
  - added the new `gpt-realtime-2` enum value to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/s2s_model` response property for the response status `201`
  - added the new `gpt-realtime-2` enum value to the request property `allOf[#/components/schemas/RetellLlmOverride]/s2s_model`
- **2026-05-08** `7dd16ddf69d8` — 4 breaking, 2 warning, 2 info
  - request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_version` list-of-types was narrowed by removing types `number` from media type `application/json`
  - request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_version` list-of-types was narrowed by removing types `number` from media type `application/json`
  - response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_version` list-of-types was widened by adding types `integer and string` to media type `application/json` of response `201`
  - response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_version` list-of-types was widened by adding types `integer and string` to media type `application/json` of response `201`
  - changed the pattern of the request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version/oneOf[subschema #2]/` from `^[a-z0-9_-]+$` to `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$`
  - changed the pattern of the request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version/oneOf[subschema #2]/` from `^[a-z0-9_-]+$` to `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$`
  - the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version/oneOf[subschema #2]/` response's property pattern was changed from `^[a-z0-9_-]+$` to `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` for the status `201`
  - the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version/oneOf[subschema #2]/` response's property pattern was changed from `^[a-z0-9_-]+$` to `^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$` for the status `201`
- **2026-05-07** `f1a0d7c1e36c` — 5 breaking, 1 info
  - removed the enum value `gemini-2.5-flash` of the request property `allOf[#/components/schemas/RetellLlmOverride]/model`
  - request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version` list-of-types was narrowed by removing types `number` from media type `application/json`
  - request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version` list-of-types was narrowed by removing types `number` from media type `application/json`
  - response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version` list-of-types was widened by adding types `integer and string` to media type `application/json` of response `201`
  - response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_version` list-of-types was widened by adding types `integer and string` to media type `application/json` of response `201`
  - removed the `gemini-2.5-flash` enum value from the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/model` response property for the response status `201`
- **2026-04-28** `1b4a9d84942a` — 2 breaking, 1 warning, 3 info
  - the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CodeTool]/code` response property's maxLength was increased from `5000` to `20000` for the response status `201`
  - the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CodeTool]/code` response property's maxLength was increased from `5000` to `20000` for the response status `201`
  - added the new `gpt-5.5` enum value to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/model` response property for the response status `201`
  - added the new `gpt-5.5` enum value to the request property `allOf[#/components/schemas/RetellLlmOverride]/model`
  - the `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CodeTool]/code` request property's maxLength was increased from `5000` to `20000`
  - the `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CodeTool]/code` request property's maxLength was increased from `5000` to `20000`
- **2026-04-20** `8ee53928bf31` — 2 breaking, 1 warning, 15 info
  - added `#/components/schemas/SmsContentTemplate` to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/SendSMSTool]/sms_content` response property `oneOf` list for the response status `201`
  - added `#/components/schemas/SmsContentTemplate` to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/SendSMSTool]/sms_content` response property `oneOf` list for the response status `201`
  - added the new `gemini-3.1-flash-lite` enum value to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/model` response property for the response status `201`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CodeTool]/enable_typing_sound`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CustomTool]/enable_typing_sound`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/MCPTool]/enable_typing_sound`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CodeTool]/enable_typing_sound`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CustomTool]/enable_typing_sound`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/MCPTool]/enable_typing_sound`
  - added the new `gemini-3.1-flash-lite` enum value to the request property `allOf[#/components/schemas/RetellLlmOverride]/model`
  - added `#/components/schemas/SmsContentTemplate` to the `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/SendSMSTool]/sms_content` request property `oneOf` list
  - added `#/components/schemas/SmsContentTemplate` to the `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/SendSMSTool]/sms_content` request property `oneOf` list
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CodeTool]/enable_typing_sound` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CustomTool]/enable_typing_sound` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/MCPTool]/enable_typing_sound` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CodeTool]/enable_typing_sound` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CustomTool]/enable_typing_sound` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/MCPTool]/enable_typing_sound` to the response with the `201` status
- **2026-04-01** `56de19127afb` — 28 info
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/conditional_prompt`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/conditional_prompt`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/conditional_prompt`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/conditional_prompt`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/SendSMSTool]/execution_message_description`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/SendSMSTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/SendSMSTool]/speak_during_execution`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/conditional_prompt`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/conditional_prompt`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/conditional_prompt`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/conditional_prompt`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/SendSMSTool]/execution_message_description`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/SendSMSTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/SendSMSTool]/speak_during_execution`
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/conditional_prompt` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/conditional_prompt` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/conditional_prompt` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/conditional_prompt` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/SendSMSTool]/execution_message_description` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/SendSMSTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/SendSMSTool]/speak_during_execution` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/conditional_prompt` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/conditional_prompt` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/conditional_prompt` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/conditional_prompt` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/SendSMSTool]/execution_message_description` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/SendSMSTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/SendSMSTool]/speak_during_execution` to the response with the `201` status
- **2026-03-19** `3aa6f6e028ef` — 2 breaking, 2 warning, 8 info
  - removed the enum value `gpt-4o-mini-realtime` of the request property `allOf[#/components/schemas/RetellLlmOverride]/s2s_model`
  - removed the enum value `gpt-4o-realtime` of the request property `allOf[#/components/schemas/RetellLlmOverride]/s2s_model`
  - added the new `gpt-5.4-mini` enum value to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/model` response property for the response status `201`
  - added the new `gpt-5.4-nano` enum value to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/model` response property for the response status `201`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/keep_current_language`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/keep_current_language`
  - added the new `gpt-5.4-mini` enum value to the request property `allOf[#/components/schemas/RetellLlmOverride]/model`
  - added the new `gpt-5.4-nano` enum value to the request property `allOf[#/components/schemas/RetellLlmOverride]/model`
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/keep_current_language` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/keep_current_language` to the response with the `201` status
  - removed the `gpt-4o-mini-realtime` enum value from the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/s2s_model` response property for the response status `201`
  - removed the `gpt-4o-realtime` enum value from the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/s2s_model` response property for the response status `201`
- **2026-03-17** `424df3aa7900` — 2 breaking, 6 warning, 28 info
  - added `#/components/schemas/CodeTool` to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/` response property `oneOf` list for the response status `201`
  - added `#/components/schemas/CodeTool` to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/` response property `oneOf` list for the response status `201`
  - removed the request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #2: Warm Transfer]/opt_out_initial_message`
  - removed the request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #2: Warm Transfer]/opt_out_initial_message`
  - removed the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #2: Warm Transfer]/opt_out_initial_message` from the response with the `201` status
  - removed the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #2: Warm Transfer]/opt_out_initial_message` from the response with the `201` status
  - added the new `gpt-5.4` enum value to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/model` response property for the response status `201`
  - added the new `gpt-realtime-1.5` enum value to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/s2s_model` response property for the response status `201`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/BridgeTransferTool]/execution_message_description`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/BridgeTransferTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/BridgeTransferTool]/speak_during_execution`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CancelTransferTool]/execution_message_description`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CancelTransferTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CancelTransferTool]/speak_during_execution`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/BridgeTransferTool]/execution_message_description`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/BridgeTransferTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/BridgeTransferTool]/speak_during_execution`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CancelTransferTool]/execution_message_description`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CancelTransferTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CancelTransferTool]/speak_during_execution`
  - added the new `gpt-5.4` enum value to the request property `allOf[#/components/schemas/RetellLlmOverride]/model`
  - added the new `gpt-realtime-1.5` enum value to the request property `allOf[#/components/schemas/RetellLlmOverride]/s2s_model`
  - added `#/components/schemas/CodeTool` to the `allOf[subschema #2]/general_tools/items/` request property `oneOf` list
  - added `#/components/schemas/CodeTool` to the `allOf[subschema #2]/states/items/tools/items/` request property `oneOf` list
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/BridgeTransferTool]/execution_message_description` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/BridgeTransferTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/BridgeTransferTool]/speak_during_execution` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CancelTransferTool]/execution_message_description` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CancelTransferTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CancelTransferTool]/speak_during_execution` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/BridgeTransferTool]/execution_message_description` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/BridgeTransferTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/BridgeTransferTool]/speak_during_execution` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CancelTransferTool]/execution_message_description` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CancelTransferTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CancelTransferTool]/speak_during_execution` to the response with the `201` status
- **2026-03-09** `8fbf8c54a142` — 12 breaking, 1 warning, 29 info
  - the `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_id` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/name` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/name` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/name` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/name` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_id` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/agent_id` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/name` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/name` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/name` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/name` request property's minLength was increased from `0` to `1`
  - the `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/agentic_transfer_config/transfer_agent/agent_id` request property's minLength was increased from `0` to `1`
  - added the new `claude-4.6-sonnet` enum value to the `allOf[#/components/schemas/RetellLlmRequest]/allOf[#/components/schemas/RetellLlmOverride]/model` response property for the response status `201`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/required`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/required`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/required`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/required`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #1: Cold Transfer]/transfer_ring_duration_ms`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #2: Warm Transfer]/transfer_ring_duration_ms`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/transfer_ring_duration_ms`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/required`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/required`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/required`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/required`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #1: Cold Transfer]/transfer_ring_duration_ms`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #2: Warm Transfer]/transfer_ring_duration_ms`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/transfer_ring_duration_ms`
  - added the new `claude-4.6-sonnet` enum value to the request property `allOf[#/components/schemas/RetellLlmOverride]/model`
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/required` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/required` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/required` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/required` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #1: Cold Transfer]/transfer_ring_duration_ms` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #2: Warm Transfer]/transfer_ring_duration_ms` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #3: Agentic Warm Transfer]/transfer_ring_duration_ms` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/BooleanAnalysisData]/required` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/EnumAnalysisData]/required` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/NumberAnalysisData]/required` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/ExtractDynamicVariableTool]/variables/items/oneOf[#/components/schemas/StringAnalysisData]/required` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #1: Cold Transfer]/transfer_ring_duration_ms` to the response with the `201` status
  - …2 more
- **2026-02-10** `0bf5cea5dfcc` — 4 info
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/keep_current_voice`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/keep_current_voice`
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/keep_current_voice` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/keep_current_voice` to the response with the `201` status
- **2026-02-06** `dfad228ab4a4` — 8 breaking, 28 info
  - the response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CustomTool]/description` became optional for the status `201`
  - the response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CustomTool]/speak_after_execution` became optional for the status `201`
  - the response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CustomTool]/description` became optional for the status `201`
  - the response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CustomTool]/speak_after_execution` became optional for the status `201`
  - response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/BookAppointmentCalTool]/event_type_id` list-of-types was widened by adding types `string` to media type `application/json` of response `201`
  - response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CheckAvailabilityCalTool]/event_type_id` list-of-types was widened by adding types `string` to media type `application/json` of response `201`
  - response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/BookAppointmentCalTool]/event_type_id` list-of-types was widened by adding types `string` to media type `application/json` of response `201`
  - response property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CheckAvailabilityCalTool]/event_type_id` list-of-types was widened by adding types `string` to media type `application/json` of response `201`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CustomTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/EndCallTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/MCPTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CustomTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/EndCallTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/MCPTool]/execution_message_type`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/execution_message_type`
  - the request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CustomTool]/description` became optional
  - the request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CustomTool]/speak_after_execution` became optional
  - the request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CustomTool]/description` became optional
  - the request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CustomTool]/speak_after_execution` became optional
  - request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/BookAppointmentCalTool]/event_type_id` list-of-types was widened by adding types `string` to media type `application/json`
  - request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CheckAvailabilityCalTool]/event_type_id` list-of-types was widened by adding types `string` to media type `application/json`
  - request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/BookAppointmentCalTool]/event_type_id` list-of-types was widened by adding types `string` to media type `application/json`
  - request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CheckAvailabilityCalTool]/event_type_id` list-of-types was widened by adding types `string` to media type `application/json`
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/AgentSwapTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/CustomTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/EndCallTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/MCPTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/AgentSwapTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/CustomTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/EndCallTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/MCPTool]/execution_message_type` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/execution_message_type` to the response with the `201` status
- **2026-01-23** `427e77039f39` — 4 info
  - added the new optional request property `allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #1: Cold Transfer]/cold_transfer_mode`
  - added the new optional request property `allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #1: Cold Transfer]/cold_transfer_mode`
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/general_tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #1: Cold Transfer]/cold_transfer_mode` to the response with the `201` status
  - added the optional property `allOf[#/components/schemas/RetellLlmRequest]/allOf[subschema #2]/states/items/tools/items/oneOf[#/components/schemas/TransferCallTool]/transfer_option/oneOf[subschema #1: Cold Transfer]/cold_transfer_mode` to the response with the `201` status

---

[Operation](https://skmtc.dev/retellai/apis/retell-sdk/docs/create-retell-llm/post.md) · [API](https://skmtc.dev/retellai/apis/retell-sdk.md) · [Page](https://skmtc.dev/retellai/apis/retell-sdk/changes/create-retell-llm/post)