Create a new outbound phone call
Request body
Example request
{
"from_number": "+14157774444",
"to_number": "+12137774445",
"override_agent_id": "oBeDLoLOeuAbiuaMFXRtDOLriTJ5tSxD",
"override_agent_version": 1,
"agent_override": {
"agent": {
"agent_name": "Jarvis",
"version_description": "Customer support agent for handling product inquiries",
"voice_id": "retell-Cimo",
"fallback_voice_ids": [
"cartesia-Cimo",
"minimax-Cimo"
],
"voice_temperature": 1,
"voice_speed": 1,
"enable_dynamic_voice_speed": true,
"enable_dynamic_responsiveness": true,
"volume": 1,
"voice_emotion": "calm",
"responsiveness": 1,
"interruption_sensitivity": 1,
"enable_backchannel": true,
"backchannel_frequency": 0.9,
"backchannel_words": [
"yeah",
"uh-huh"
],
"reminder_trigger_ms": 10000,
"reminder_max_count": 2,
"ambient_sound_volume": 1,
"language": "en-US",
"webhook_url": "https://webhook-url-here",
"webhook_timeout_ms": 10000,
"boosted_keywords": [
"retell",
"kroger"
],
"data_storage_setting": "everything",
"data_storage_retention_days": 30,
"opt_in_signed_url": true,
"signed_url_expiration_ms": 86400000,
"pronunciation_dictionary": [
{
"word": "actually",
"alphabet": "ipa",
"phoneme": "ˈæktʃuəli"
}
],
"end_call_after_silence_ms": 600000,
"max_call_duration_ms": 3600000,
"voicemail_message": "Hi, please give us a callback.",
"voicemail_detection_timeout_ms": 30000,
"voicemail_option": {
"action": {
"type": "static_text",
"text": "Please give us a callback tomorrow at 10am."
}
},
"ivr_option": {
"action": {
"type": "hangup"
}
},
"call_screening_option": {
"agent_identity": "Acme Health scheduling team",
"call_purpose": "confirming your appointment for tomorrow"
},
"post_call_analysis_data": [
{
"type": "string",
"name": "customer_name",
"description": "The name of the customer.",
"examples": [
"John Doe",
"Jane Smith"
]
}
],
"analysis_successful_prompt": "The agent finished the task and the call was complete without being cutoff.",
"analysis_summary_prompt": "Summarize the outcome of the conversation in two sentences.",
"analysis_user_sentiment_prompt": "Evaluate the user's sentiment based on their tone and satisfaction level.",
"begin_message_delay_ms": 1000,
"ring_duration_ms": 30000,
"stt_mode": "fast",
"vocab_specialization": "general",
"allow_user_dtmf": true,
"user_dtmf_options": {
"termination_key": "#"
},
"denoising_mode": "noise-cancellation",
"timezone": "America/New_York"
},
"retell_llm": {
"s2s_model": "gpt-realtime-1.5",
"model_high_priority": true,
"tool_call_strict_mode": true,
"kb_config": {
"top_k": 3,
"filter_score": 0.6
},
"begin_after_user_silence_ms": 2000,
"begin_message": "Hey I am a virtual assistant calling from Retell Hospital."
},
"conversation_flow": {
"model_temperature": 0.7,
"tool_call_strict_mode": true,
"knowledge_base_ids": [
"kb_001",
"kb_002"
],
"kb_config": {
"top_k": 3,
"filter_score": 0.6
},
"start_speaker": "agent",
"begin_after_user_silence_ms": 2000
}
},
"retell_llm_dynamic_variables": {
"customer_name": "John Doe"
},
"custom_sip_headers": {
"X-Custom-Header": "Custom Value"
},
"ignore_e164_validation": true
}Response
Successfully made an outbound call.
Example response
{
"call_type": "phone_call",
"from_number": "+12137771234",
"to_number": "+12137771235",
"direction": "inbound",
"telephony_identifier": {
"twilio_call_sid": "CA5d0d0d8047bf685c3f0ff980fe62c123"
},
"call_id": "Jabr9TXYYJHfvl6Syypi88rdAHYHmcq6",
"agent_id": "oBeDLoLOeuAbiuaMFXRtDOLriTJ5tSxD",
"agent_name": "My Agent",
"agent_version": 1,
"call_status": "registered",
"retell_llm_dynamic_variables": {
"customer_name": "John Doe"
},
"collected_dynamic_variables": {
"last_node_name": "Test node"
},
"custom_sip_headers": {
"X-Custom-Header": "Custom Value"
},
"data_storage_setting": "everything",
"opt_in_signed_url": true,
"start_timestamp": 1703302407333,
"end_timestamp": 1703302428855,
"transfer_end_timestamp": 1703302628855,
"duration_ms": 10000,
"transcript": "Agent: hi how are you doing?\nUser: Doing pretty well. How are you?\nAgent: That's great to hear! I'm doing well too, thanks! What's up?\nUser: I don't have anything in particular.\nAgent: Got it, just checking in!\nUser: Alright. See you.\nAgent: have a nice day\n",
"transcript_object": [
{
"role": "agent",
"content": "hi how are you doing?",
"words": [
{
"word": "hi",
"start": 0.7,
"end": 1.3
}
]
}
],
"transcript_with_tool_calls": [
{
"role": "agent",
"content": "hi how are you doing?",
"words": [
{
"word": "hi",
"start": 0.7,
"end": 1.3
}
]
}
],
"scrubbed_transcript_with_tool_calls": [
{
"role": "agent",
"content": "hi how are you doing?",
"words": [
{
"word": "hi",
"start": 0.7,
"end": 1.3
}
]
}
],
"recording_url": "https://retellai.s3.us-west-2.amazonaws.com/Jabr9TXYYJHfvl6Syypi88rdAHYHmcq6/recording.wav",
"recording_multi_channel_url": "https://retellai.s3.us-west-2.amazonaws.com/Jabr9TXYYJHfvl6Syypi88rdAHYHmcq6/recording_multichannel.wav",
"scrubbed_recording_url": "https://retellai.s3.us-west-2.amazonaws.com/Jabr9TXYYJHfvl6Syypi88rdAHYHmcq6/recording.wav",
"scrubbed_recording_multi_channel_url": "https://retellai.s3.us-west-2.amazonaws.com/Jabr9TXYYJHfvl6Syypi88rdAHYHmcq6/recording_multichannel.wav",
"public_log_url": "https://retellai.s3.us-west-2.amazonaws.com/Jabr9TXYYJHfvl6Syypi88rdAHYHmcq6/public_log.txt",
"knowledge_base_retrieved_contents_url": "https://retellai.s3.us-west-2.amazonaws.com/Jabr9TXYYJHfvl6Syypi88rdAHYHmcq6/kb_retrieved_contents.txt",
"latency": {
"e2e": {
"p50": 800,
"p90": 1200,
"p95": 1500,
"p99": 2500,
"max": 2700,
"min": 500,
"num": 10
},
"asr": {
"p50": 800,
"p90": 1200,
"p95": 1500,
"p99": 2500,
"max": 2700,
"min": 500,
"num": 10
},
"llm": {
"p50": 800,
"p90": 1200,
"p95": 1500,
"p99": 2500,
"max": 2700,
"min": 500,
"num": 10
},
"llm_websocket_network_rtt": {
"p50": 800,
"p90": 1200,
"p95": 1500,
"p99": 2500,
"max": 2700,
"min": 500,
"num": 10
},
"tts": {
"p50": 800,
"p90": 1200,
"p95": 1500,
"p99": 2500,
"max": 2700,
"min": 500,
"num": 10
},
"knowledge_base": {
"p50": 800,
"p90": 1200,
"p95": 1500,
"p99": 2500,
"max": 2700,
"min": 500,
"num": 10
},
"s2s": {
"p50": 800,
"p90": 1200,
"p95": 1500,
"p99": 2500,
"max": 2700,
"min": 500,
"num": 10
}
},
"transfer_destination": "+12137771234",
"call_analysis": {
"call_summary": "The agent called the user to ask question about his purchase inquiry. The agent asked several questions regarding his preference and asked if user would like to book an appointment. The user happily agreed and scheduled an appointment next Monday 10am.",
"user_sentiment": "Positive",
"call_successful": true
},
"call_cost": {
"product_costs": [
{
"product": "elevenlabs_tts",
"unit_price": 1,
"cost": 60
}
],
"total_duration_seconds": 60,
"total_duration_unit_price": 1,
"combined_cost": 70
}
}Changes
Changed in 21 of the 28 revisions of this API.941966
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added
InjectedUtteranceto theallOf[V2CallBase]/scrubbed_transcript_with_tool_calls/items/response propertyoneOflist for the response status201response-property-one-of-added
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added
InjectedUtteranceto theallOf[V2CallBase]/transcript_with_tool_calls/items/response propertyoneOflist for the response status201response-property-one-of-added
- ●
changed the pattern of the request property
override_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+)$)[a-z][a-z0-9_-]{0,19})$request-property-pattern-changed
- ●
added the new
no_concurrency_fallbackenum value to theallOf[V2CallBase]/disconnection_reasonresponse property for the response status201response-property-enum-value-added
- ▲
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added
SmsUtteranceto theallOf[V2CallBase]/scrubbed_transcript_with_tool_calls/items/response propertyoneOflist for the response status201response-property-one-of-added
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added
SmsUtteranceto theallOf[V2CallBase]/transcript_with_tool_calls/items/response propertyoneOflist for the response status201response-property-one-of-added
- ●
removed the request property
agent_override/agent/is_publicrequest-property-removed
- ▲
- ▲
the
retell_llm_dynamic_variables/additionalProperties/request property type/format changed from/tostring/request-property-type-changed
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the
allOf[V2CallBase]/collected_dynamic_variables/additionalProperties/response's property type/format changed from/tostring/for status201response-property-type-changed
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the
allOf[V2CallBase]/retell_llm_dynamic_variables/additionalProperties/response's property type/format changed from/tostring/for status201response-property-type-changed
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added the new
gpt-realtime-2enum value to the request propertyagent_override/retell_llm/s2s_modelrequest-property-enum-value-added
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added the new
s2.1-proenum value to the request propertyagent_override/agent/voice_modelrequest-property-enum-value-added
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added the new
sonic-3.5enum value to the request propertyagent_override/agent/voice_modelrequest-property-enum-value-added
- ○
- ●
changed the pattern of the request property
override_agent_version/oneOf[subschema #2]/from^[a-z0-9_-]+$to^(latest|(?!(?:v\d+)$)[a-z][a-z0-9_-]{0,19})$request-property-pattern-changed
- ●
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removed the enum value
gemini-2.5-flashof the request propertyagent_override/agent/post_call_analysis_modelrequest-property-enum-value-removed
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removed the enum value
gemini-2.5-flashof the request propertyagent_override/conversation_flow/model_choice/oneOf[ModelChoiceCascading]/modelrequest-property-enum-value-removed
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removed the enum value
gemini-2.5-flashof the request propertyagent_override/retell_llm/modelrequest-property-enum-value-removed
- ○
added the new optional request property
agent_override/agent/allow_dtmf_interruptionnew-optional-request-property
- ○
added the new optional request property
agent_override/agent/call_screening_optionnew-optional-request-property
- ○
added the new optional request property
agent_override/agent/ivr_option/detection_promptnew-optional-request-property
- ○
added the new optional request property
agent_override/agent/voicemail_option/detection_promptnew-optional-request-property
- ○
request property
override_agent_versionlist-of-types was widened by adding typesstringto media typeapplication/jsonrequest-property-list-of-types-widened
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added
AsrProviderto theagent_override/agent/custom_stt_config/providerrequest propertyallOflistrequest-property-all-of-added
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removed the enum value
azureof the request propertyagent_override/agent/custom_stt_config/providerrequest-property-enum-value-removed
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removed the enum value
deepgramof the request propertyagent_override/agent/custom_stt_config/providerrequest-property-enum-value-removed
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removed the enum value
sonioxof the request propertyagent_override/agent/custom_stt_config/providerrequest-property-enum-value-removed
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the
agent_override/agent/custom_stt_config/providerrequest property type/format changed fromstring/to/request-property-type-changed
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added the new
gpt-5.5enum value to the request propertyagent_override/agent/post_call_analysis_modelrequest-property-enum-value-added
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added the new
gpt-5.5enum value to the request propertyagent_override/conversation_flow/model_choice/oneOf[ModelChoiceCascading]/modelrequest-property-enum-value-added
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added the new
gpt-5.5enum value to the request propertyagent_override/retell_llm/modelrequest-property-enum-value-added
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removed the enum value
af-ZAof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
ar-SAof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
az-AZof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
bg-BGof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
bs-BAof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
ca-ESof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
cs-CZof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
cy-GBof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
da-DKof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
de-DEof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
el-GRof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
en-AUof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
en-GBof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
en-INof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
en-NZof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
en-USof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
es-419of the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
es-ESof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
fa-IRof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
fi-FIof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
fil-PHof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
fr-CAof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
fr-FRof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
gl-ESof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
he-ILof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
hi-INof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
hr-HRof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
hu-HUof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
hy-AMof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
id-IDof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
is-ISof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
it-ITof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
ja-JPof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
kk-KZof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
kn-INof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
ko-KRof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
lt-LTof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
lv-LVof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
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removed the enum value
mk-MKof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
mr-INof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
ms-MYof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
multiof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
ne-NPof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
nl-BEof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
nl-NLof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
no-NOof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
pl-PLof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
pt-BRof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
pt-PTof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
ro-ROof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
ru-RUof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
sk-SKof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
sl-SIof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
sr-RSof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
sv-SEof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
sw-KEof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
ta-INof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
th-THof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
tr-TRof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
uk-UAof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
ur-INof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
vi-VNof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
yue-CNof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
removed the enum value
zh-CNof the request propertyagent_override/agent/languagerequest-property-enum-value-removed
- ▲
the
agent_override/agent/languagerequest property type/format changed fromstring/to/request-property-type-changed
- ○
added
LanguageLegacysubschema #2to theagent_override/agent/languagerequest propertyoneOflistrequest-property-one-of-added
- ▲
- ●
removed the request property
agent_override/agent/normalize_for_speechrequest-property-removed
- ●
added the new
manual_stoppedenum value to theallOf[V2CallBase]/disconnection_reasonresponse property for the response status201response-property-enum-value-added
- ○
added the new
gemini-3.1-flash-liteenum value to the request propertyagent_override/agent/post_call_analysis_modelrequest-property-enum-value-added
- ○
added the new
gemini-3.1-flash-liteenum value to the request propertyagent_override/conversation_flow/model_choice/oneOf[ModelChoiceCascading]/modelrequest-property-enum-value-added
- ○
added the new
gemini-3.1-flash-liteenum value to the request propertyagent_override/retell_llm/modelrequest-property-enum-value-added
- ○
added the new
s2-proenum value to the request propertyagent_override/agent/voice_modelrequest-property-enum-value-added
- ○
added the new
sonioxenum value to the request propertyagent_override/agent/custom_stt_config/providerrequest-property-enum-value-added
- ○
added the optional property
allOf[V2CallBase]/scrubbed_transcript_with_tool_calls/items/oneOf[NodeTransitionUtterance]/transition_typeto the response with the201statusresponse-optional-property-added
- ○
added the optional property
allOf[V2CallBase]/transcript_with_tool_calls/items/oneOf[NodeTransitionUtterance]/transition_typeto the response with the201statusresponse-optional-property-added
- ●
- ▲
removed
StringAnalysisDataEnumAnalysisDataBooleanAnalysisDataNumberAnalysisDatafrom theagent_override/agent/post_call_analysis_data/items/request propertyoneOflistrequest-property-one-of-removed
- ○
added the new optional request property
agent_override/agent/handbook_confignew-optional-request-property
- ○
added the new optional request property
agent_override/agent/timezonenew-optional-request-property
- ○
added
AnalysisDataCallPresetAnalysisDatato theagent_override/agent/post_call_analysis_data/items/request propertyoneOflistrequest-property-one-of-added
- ▲