Agents API

The Agents API is a set of REST endpoints for building and shipping PolyAI agents without the UI. It covers the full agent lifecycle: create the agent, branch for parallel work, edit behavior and knowledge, provision telephony, publish through environments, and tweak runtime values after launch.

Use it when you want to automate agent setup from your own tooling — CRM workflows, CCaaS provisioning, internal platforms, or coding agents — instead of clicking through Agent Studio.

How it differs from the Conversations API

The Agents API is the build and deploy layer. The Conversations API is the read and analyze layer. They’re separate services with separate base URLs, auth, and audiences.

If you want to ship an agent change, use the Agents API. If you want to know what happened in a call, use the Conversations API. See Getting started for the full distinction across all API families.

Resource model

The Agents API is organized around a small set of nested resources:

account
 ├── agent                  # top-level agent resource (created/listed under account)
 └── voice-library          # account-scoped voice catalog (register, list, sample)
agent
 ├── branch                 # isolated working copy
 │    ├── behavior          # system prompt and interaction rules
 │    ├── knowledge-base    # topics and RAG
 │    ├── attributes        # variant dimensions
 │    └── variants          # site-specific overrides
 ├── deployment             # published version per environment
 ├── telephony
 │    ├── connector         # voice-infra binding
 │    └── phone-number      # E.164 number routed to a connector
 └── real-time-config       # runtime values editable without publishing

Agents and voice library entries are scoped to an account. Everything inside an agent except deployments, telephony, and real-time configs is scoped to a branch. The default branch is main; create additional branches for parallel development and merge them back.

Base URL

The Agents API uses the same regional base URL family as Alerts and Webhooks:

Most Agents API paths are prefixed with /v1/agents/{agentId}/…. Account-scoped endpoints (listing/creating agents, voice library) are prefixed with /v1/accounts/{accountId}/….

Authentication

All endpoints authenticate with an API key sent in the x-api-key header. Keys are scoped to a workspace.

curl https://api.us.poly.ai/v1/accounts/ACCOUNT_ID/agents \
  -H "x-api-key: YOUR_API_KEY"

Quick start

1. Create an agent

curl -X POST https://api.us.poly.ai/v1/accounts/ACCOUNT_ID/agents \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Support Agent",
    "description": "Handles Tier 1 support for the US market"
  }'

The response includes an agentId and a default main branch.

2. Update the agent’s behavior

curl -X PATCH https://api.us.poly.ai/v1/agents/AGENT_ID/branches/main/behavior \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "behavior": "You are a friendly, concise support agent..."
  }'

3. Add a knowledge base topic

curl -X POST https://api.us.poly.ai/v1/agents/AGENT_ID/branches/main/knowledge-base/topics \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Password reset",
    "content": "Users can reset their password by..."
  }'

4. Publish to sandbox

curl -X POST https://api.us.poly.ai/v1/agents/AGENT_ID/deployments/publish \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "environment": "sandbox" }'

5. Promote to pre-release, then live

curl -X POST https://api.us.poly.ai/v1/agents/AGENT_ID/deployments/DEPLOYMENT_ID/promote \
  -H "x-api-key: YOUR_API_KEY"

Environments

Deployments run in one of three environments:

Use publish to push a draft into sandbox, then promote to move through pre-release and live. Use rollback to revert a deployment. See Environments for the full model.

Branches

Branches are isolated working copies of an agent. Create a branch for any non-trivial change:

curl -X POST https://api.us.poly.ai/v1/agents/AGENT_ID/branches \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "name": "experiment-new-greeting" }'

Merge back to main when you’re ready:

curl -X POST https://api.us.poly.ai/v1/agents/AGENT_ID/branches/BRANCH_ID/merge \
  -H "x-api-key: YOUR_API_KEY"

Real-time configs

Real-time configs let you change runtime values (opening hours, seasonal messaging, holiday flags) without a publish cycle. Updates take effect immediately.

Define a JSON Schema for a config page, then PATCH variables against it:

curl -X PATCH https://api.us.poly.ai/v1/agents/AGENT_ID/real-time-configs/live/variables \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "variables": { "open_hour": 8, "close_hour": 22 } }'

Variants

Variants let you run one agent across many sites — hotel chains, restaurant groups, franchises — with site-specific values (phone number, address, hours). Define attributes (dimensions), then create variants (combinations).

See Variants for the conceptual model.

Error responses

Example error response

{
  "message": "Validation failed",
  "errors": [
    {
      "field": "name",
      "message": "must be between 1 and 128 characters"
    }
  ]
}

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