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Retell AI Update Agent API

The Update Agent API from Retell AI — 1 operation(s) for update agent.

Retell AI Update Agent API is one of 78 APIs that Retell AI publishes on the APIs.io network, described by a machine-readable OpenAPI specification and an AsyncAPI event-driven specification.

Tagged areas include Update Agent. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, an AsyncAPI specification, and pricing.

This API exposes 1 operation across 1 path, and defines 28 schemas. It is described by OpenAPI 3.2.0, at version 3.0.0.

Requests are made against a single base URL, https://api.retellai.com.

1 operations 1 paths 28 schemas 1 PATCH

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
3.0.0
Base URL
https://api.retellai.com
Authentication
HTTP Bearer
License
Resource Areas
1

Authentication & Security 1

Retell AI Update Agent API declares 1 security scheme for authenticating requests. It accepts HTTP bearer tokens (string) (api_key). By default, every request must be authenticated.

  • api_key — Authentication header containing API key (find it in dashboard). The format is "Bearer YOURAPIKEY"

Paths & Operations 1

Across 1 path, the API surfaces 1 operation — 1 PATCH. Each is listed below with its method, path, parameters, and response codes.

Update Agent 1
PATCH
/update-agent/{agent_id}
Update an existing agent's latest draft version
updateAgent 2 params body → 200400401412422500

Schemas 28

The contract defines 28 schemas that model the data the API accepts and returns. The most detailed are AgentRequest (57 properties), VoiceHandbookConfig (9 properties), EnumAnalysisData (6 properties), StringAnalysisData (6 properties). Each schema is shown below with its type and property counts.

AnalysisData
IvrAction
VoicemailActionBridgeTransfer
object
1 property 1 required
EnumAnalysisData
object
6 properties 4 required
ResponseEngineRetellLm
object
3 properties 2 required
NumberAnalysisData
object
5 properties 3 required
VoicemailActionHangup
object
1 property 1 required
PostCallAnalysisData
Post-call analysis item (custom data or voice preset). Use for voice agent postcallanalysisdata; validates only call presets (callsummary, callsuccessful, user…
ResponseEngineCustomLm
object
2 properties 2 required
StringAnalysisData
object
6 properties 3 required
BooleanAnalysisData
object
5 properties 3 required
LanguageLegacy
Legacy single-string language format. Accepts any concrete locale from Language, plus the special scalar value multi for multilingual support. If unset, will u…
AgentRequest
object
57 properties
VoicemailActionStaticText
object
2 properties 2 required
VoiceHandbookConfig
object
Behavior presets for voice agents. All presets are available.
9 properties
VoicemailAction
VoicemailActionPrompt
object
2 properties 2 required
IvrActionHangup
object
1 property 1 required
GuardrailConfig
object
2 properties
Language
string
Specifies what language (and dialect) the agent will operate in. For instance, selecting en-GB optimizes speech recognition for British English and indexes kno…
ResponseEngineConversationFlow
object
3 properties 2 required
PIIConfig
object
2 properties 2 required
CallScreeningOption
objectnull
If this option is set, the agent prompt will include call screen handling instructions for identity and call purpose questions. Set this to null to disable cal…
2 properties 2 required
AgentResponse
AsrProvider
string
ASR provider name.
ResponseEngine
NullableLLMModel
stringnull
Available LLM models for agents.
CallPresetAnalysisData
object
System preset for post-call analysis (voice agents). Use in postcallanalysisdata to override prompts or mark fields optional.
5 properties 2 required

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

retell-ai-update-agent-api-openapi.yml Raw ↑

Other APIs Retell AI publishes across the network.

Retell AI Add Community Voice API
Retell AI Add Knowledge Base Sources API
Retell AI Agent Playground Completion API
Retell AI Clone Voice API
Retell AI Create Agent API
Retell AI Create Agent Version API
Retell AI Create Batch Call API
Retell AI Create Batch Test API
Retell AI Create Chat Agent API
Retell AI Create Chat API
Retell AI Create Chat Completion API
Retell AI Create Conversation Flow API
Where this information came from

This is an independent, third-party profile of Retell AI Update Agent API, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.

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