review.yml

aid: cresta
name: Cresta
review_date: '2026-05-29'
scope: Public WebSocket API availability for agent-assist suggestions or transcript streaming
reviewer: API Evangelist
sources:
  - https://docs.cresta.com
  - https://docs.cresta.com/sitemap.md
  - https://developers.cresta.com
  - https://cresta.com/ai-platform
  - https://cresta.com/agent-assist
  - https://cresta.com/ai-agent
  - https://cresta.com/blog/the-three-pillars-of-voice-integration-building-hybrid-ai-contact-centers-that-work-with-your-existing-infrastructure
  - https://cresta.com/blog/understanding-crestas-voice-platform-the-voice-stack
findings:
  public_websocket_api: false
  public_openapi: false
  public_webhooks_documented: false
  public_sdk_release: false
  public_developer_self_service: false
  authentication_required_for_api_docs: true
summary: >-
  Cresta does not expose a documented public WebSocket API for agent-assist
  suggestions or transcript streaming. The Cresta documentation portal at
  docs.cresta.com is end-user / customer support content (welcome, walkthrough,
  trainings, support ticket flows) — its sitemap surfaces no public API,
  WebSocket, webhook, SDK, streaming, real-time, events, subscription, or
  developer integration paths. The developers.cresta.com landing page only
  states that Cresta "provides SDKs and APIs to facilitate integrating with
  Cresta conversation services" and directs prospective integrators to
  "request a Cresta demo and learn more about the Cresta SDK and API
  documentation and references" — full technical references sit behind a
  customer / partner login.
websocket_context: >-
  Cresta does describe WebSocket usage in its public engineering blog, but
  exclusively as an INBOUND audio-ingestion path: CCaaS platforms push audio
  into Cresta via WebSocket streaming, gRPC streams, or raw RTP for low-latency
  real-time processing. This is the "push mode" ingestion side of the Voice
  Stack (received by Cresta's gowalter service), not an outbound public
  WebSocket that external consumers can subscribe to for agent-assist
  recommendations or transcripts. Agent surfacing of transcripts and assist
  events happens through Cresta's internal apiserver to Cresta-authored agent
  UIs / embedded surfaces, not via a documented public WS endpoint.
documented_surfaces:
  - kind: Embedded Agent UI / Agent Desktop integration
    public: false
    notes: >-
      Cresta delivers agent-assist suggestions and transcripts into agent
      desktops via embedded Cresta surfaces wired into CCaaS desktops (Five9,
      Genesys, NICE CXone, Amazon Connect, Twilio Flex, Talkdesk, etc.),
      configured per customer.
  - kind: Voice ingestion (inbound)
    public: false
    notes: >-
      WebSocket streaming, gRPC streams, raw RTP, SIPREC, SIP trunking, PSTN
      transfer, and CCaaS native streaming are supported as transports for
      audio into Cresta. These are integration patterns negotiated with each
      CCaaS or SBC partner — not a published public WS API.
  - kind: AI Agent tool access
    public: false
    notes: >-
      Cresta AI Agent supports API-based function calling and Model Context
      Protocol (MCP) for standardized outbound tool access. This is calling
      customer / partner tools, not a public Cresta API.
  - kind: REST API
    public: false
    notes: >-
      Referenced generically as "APIs to facilitate integrating with Cresta
      conversation services" but no public reference, base URL, endpoints,
      authentication scheme, or OpenAPI specification is published. Access is
      gated behind customer / partner engagement.
  - kind: Webhooks
    public: false
    notes: >-
      No public webhook catalog, event list, payload schemas, or subscription
      mechanism is documented on docs.cresta.com or developers.cresta.com.
  - kind: SDK
    public: false
    notes: >-
      Cresta SDK is referenced on developers.cresta.com as "comprehensive
      public facing SDK" but no package, repository, version, language, or
      reference material is reachable without a customer / partner login.
asyncapi_recommended: false
openapi_recommended: false
reason_no_spec: >-
  No public, stable, addressable WebSocket / streaming endpoint or message
  catalog is documented. Authoring an AsyncAPI spec would require fabricating
  channels, operations, and message schemas that Cresta has not published.
  Per project rules (no fabrication), only this review.yml is produced and
  no asyncapi/ or openapi/ artifact is created.
apis_yml_updated: false
apis_yml_reason: >-
  Existing apis.yml already accurately characterizes Cresta as having a
  private, gated API/SDK with no public OpenAPI, no public SDK release, and
  no public developer self-service portal. No new public surface was
  discovered that warrants an update.