Zelto Agents API

openapi: 3.2.0
info:
  title: Zelto REST Agents API
  version: v1
  description: Programmatic access to your Zelto organization. Every endpoint is scoped to the organization the API key belongs to. Mint a key at Settings → Integrations → API Call Upload.
servers:
- url: https://api.zelto.ai
  description: Production
security:
- bearerAuth: []
tags:
- name: Agents
  description: Voice and chat bots normalised through Zelto's ingestion pipeline.
paths:
  /v1/agents:
    get:
      summary: List agents
      operationId: listAgents
      tags:
      - Agents
      parameters:
      - $ref: '#/components/parameters/Limit'
      - $ref: '#/components/parameters/Cursor'
      responses:
        '200':
          description: Page of agents.
          content:
            application/json:
              schema:
                allOf:
                - $ref: '#/components/schemas/PageEnvelope'
                - type: object
                  properties:
                    data:
                      type: array
                      items:
                        $ref: '#/components/schemas/Agent'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /v1/agents/{id}:
    get:
      summary: Get an agent
      operationId: getAgent
      tags:
      - Agents
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
          format: uuid
      responses:
        '200':
          description: The agent.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Agent'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
  /v1/agents/{id}/versions:
    post:
      summary: Register an agent version
      operationId: registerAgentVersion
      tags:
      - Agents
      description: Register a release prompt and context before calls arrive. Requires a key belonging to an organization owner or admin. Repeating the same values returns the existing ID; changes require a new label. Send that label as version on every call for the same agent. Does not deploy the agent or route traffic. See /docs/agent-versions.
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
          format: uuid
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/RegisterAgentVersion'
      responses:
        '201':
          description: Version registered.
          content:
            application/json:
              schema:
                type: object
                required:
                - id
                - created
                properties:
                  id:
                    type: string
                    format: uuid
                  created:
                    type: boolean
        '200':
          description: Identical version already registered.
          content:
            application/json:
              schema:
                type: object
                required:
                - id
                - created
                properties:
                  id:
                    type: string
                    format: uuid
                  created:
                    type: boolean
        '400':
          description: Invalid input or human agent.
        '403':
          description: Requires an organization owner or admin.
        '409':
          description: The label already exists with a different prompt or configuration. Use a new label.
        '500':
          description: Could not register the version.
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
components:
  schemas:
    Agent:
      type: object
      required:
      - id
      - name
      - description
      - externalId
      - provider
      - createdAt
      - updatedAt
      properties:
        id:
          type: string
          format: uuid
        name:
          type: string
        description:
          type: string
          nullable: true
        externalId:
          type: string
          nullable: true
        provider:
          type: string
          nullable: true
          description: '`vapi`, `retell`, `speechify`, `livekit`, or null for direct uploads.'
        createdAt:
          type: string
          format: date-time
        updatedAt:
          type: string
          format: date-time
    AgentVersionConfig:
      type: object
      additionalProperties: true
      description: Complete version context as a JSON object, up to 64 KiB serialized as UTF-8. Can include llm, stt, tts, tools, workflows, retrieval, and custom settings. Records context only; does not deploy or execute this configuration. Do not include secrets.
    Error:
      type: object
      required:
      - error
      properties:
        error:
          type: string
          description: Human-readable error message, e.g. Unauthorized or Validation failed.
        message:
          type: string
        details:
          type: object
          additionalProperties: true
    PageEnvelope:
      type: object
      required:
      - data
      - nextCursor
      properties:
        data:
          type: array
          items: {}
        nextCursor:
          type: string
          nullable: true
    RegisterAgentVersion:
      type: object
      required:
      - version
      properties:
        version:
          type: string
          minLength: 1
          maxLength: 255
          description: 'Case-sensitive release label after trimming whitespace. The draft: and generated: prefixes are reserved.'
        systemPrompt:
          type: string
          maxLength: 200000
        config:
          $ref: '#/components/schemas/AgentVersionConfig'
  responses:
    Unauthorized:
      description: Missing or invalid API key.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    NotFound:
      description: Resource not found in your organization.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  parameters:
    Limit:
      name: limit
      in: query
      required: false
      description: Items per page. Default 50, max 200.
      schema:
        type: integer
        minimum: 1
        maximum: 200
        default: 50
    Cursor:
      name: cursor
      in: query
      required: false
      description: Opaque pagination cursor. Pass the `nextCursor` returned by the previous page.
      schema:
        type: string
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: 'Send `Authorization: Bearer YOUR_API_KEY`. The key resolves to a single organization.'