Skip to content
Voice Agent CLI

Retell

Retell is the first and only provider implemented today. The integration is built on the official retell-sdk, pinned exactly to 6.0.1 in the root package.json and package-lock.json as of 2026-09-29.

The vac retell namespace covers:

Area Command groups
Authentication login
Agents and prompts agents, agent, agent-publish, prompts, tools, tests
Calls calls, transcripts, batch-calls, exports, concurrency
Response engines llms, flows, flow-components
Chat chat-agents, chats, playground
Other resources phone-numbers, voices, kb

Use generated help for the exact operations and flags because command groups do not share a universal CRUD surface:

Terminal window
vac retell --help
vac retell phone-numbers --help

Most commands use the SDK client in src/providers/retell/services/retell-client.ts. Live-call updates and agent environment tags use the same authenticated client with explicit Retell HTTP paths because those operations are not exposed through the pinned SDK’s resource helpers.

Inspect and assign environment tags through the agent namespace:

Terminal window
vac retell agents tags get agent_123 prod
vac retell agents tags assign agent_123 prod --agent-version 4 --dry-run
vac retell agents tags assign agent_123 prod --agent-version 4
vac retell agents tags assign agent_123 staging \
  --dynamic-variables '{"base_url":"https://staging.example.com"}' \
  --dry-run

The assignment command requires an existing tag. --agent-version moves it. Dynamic-variable flags merge into the selected tag unless --replace is set, and the other tags stay as they are. PATCH /update-agent-root/{agent_id} sends the complete tag map. The command verifies the selected tag after the update. Secret-looking variable names are masked in command output. Moving prod, or changing variables on a tag that traffic uses, takes effect immediately.

Phone-number bindings can resolve through a tag instead of a fixed numeric version:

Terminal window
vac retell phone-numbers update +14157774444 \
  --inbound-agent agent_123 \
  --inbound-agent-version prod

The paired outbound flags are --outbound-agent and --outbound-agent-version. Read the number before and after the update because replacing a single-agent binding is an immediate routing change.

Read API compatibility before updating the SDK or sending raw Retell payloads.