# Transfer an AI Phone Call to the Owner with AgentLine - **Canonical URL:** https://agentline.cloud/blog/ai-call-transfer-to-owner-agentline - **HTML:** https://agentline.cloud/blog/ai-call-transfer-to-owner-agentline - **Markdown:** https://agentline.cloud/blog/ai-call-transfer-to-owner-agentline.md - **Date:** 2026-10-18 - **Updated:** 2026-10-18 - **Author:** Sameer Srivastava - **Read time:** 3 min read - **Tags:** `Voice`, `API`, `Guide`, `Retell`, `Support` > Configure owner_phone, test a human escalation, and understand the difference between AgentLine's owner transfer and a warm handoff. --- AgentLine can connect a live caller to the agent's configured owner_phone when a human is needed. This is an owner-only transfer, not a general destination-routing API or a warm handoff with a private briefing. If your requirement is to brief a sales representative before joining the caller, evaluate a platform with an explicit warm-transfer feature. ## Configure the destination Use an owner-controlled E.164 phone number. Set owner_phone on agent creation or update it with PATCH /v1/agents/{id}. Leave transfer_number unset: the service derives it from owner_phone. If supplied, transfer_number must match owner_phone; a different destination is rejected. In Bash, set AGENTLINE_API_KEY privately and replace AGENT_ID and OWNER_PHONE before running: ```bash curl --fail-with-body -X PATCH https://api.agentline.cloud/v1/agents/AGENT_ID -H "Authorization: Bearer $AGENTLINE_API_KEY" -H "Content-Type: application/json" -d '{"owner_phone":"OWNER_PHONE"}' ``` The API also uses owner_phone for owner-related task behavior. Treat changing it as a routing change and confirm the correct person controls the destination. Read back the agent configuration before testing. ## Give the assistant a clear escalation rule Keep the ordinary support instructions in the full agent prompt. Add a rule such as: answer routine questions from approved information; if the caller asks for a person or the request cannot be handled, connect them to the owner. Tell the caller what is happening before the handoff. Updating system_prompt replaces the previous instructions, so preserve the rest of your prompt. The hosted voice path handles the transfer signal. Your webhook should not invent a new transfer endpoint or return a caller-selected destination. The owner destination is configured ahead of time. Calls already involving the owner are protected against transferring back to that same person. ## Test success and failure separately 1. Provision and configure a test agent using the [REST walkthrough](/blog/agentline-api-developer-walkthrough). 2. Call its number from a different phone while the owner is available. Ask to speak with a human and check that the owner receives the call. 3. Repeat while the owner does not answer. Confirm the caller hears the failure response rather than a claim that someone has joined. 4. Ask an ordinary question that the agent can answer. Confirm it stays in the conversation. 5. Inspect the transcript and call status. Keep test observations separate from configuration validation. These are suggested acceptance tests, not results of a published call benchmark. A configured owner number alone does not guarantee pickup, availability, or a successful bridge. ## When a warm transfer is required [Retell documents cold, warm and agentic warm transfers](https://docs.retellai.com/build/single-multi-prompt/transfer-call), including recipient briefing options. That is a different workflow from AgentLine's direct owner handoff. Evaluate who receives the call, whether they hear a summary first, and what the caller experiences when nobody answers. For qualification workflows, see [AgentLine vs Retell for lead follow-up](/blog/agentline-vs-retell-lead-follow-up). Configuration reviewed against [AgentLine API schema](https://api.agentline.cloud/openapi.json) and [agent skill](/skill.md) and AgentLine's owner-transfer implementation. ## Frequently Asked Questions **Can AgentLine transfer a live call to a person?** Yes, to the configured owner_phone. The destination is owner-only; transfer_number must be omitted or match that owner phone. **Does AgentLine provide a warm-transfer briefing?** The documented owner-transfer flow does not provide a private briefing before connecting the caller. Evaluate a dedicated warm-transfer feature if that is required. **Do I call a transfer REST endpoint?** The documented setup uses owner_phone on the agent. The hosted voice flow handles the transfer during the conversation; this guide does not require a separate call-transfer REST endpoint. --- ## Related guides - [Choose an AI Phone Voice with the AgentLine API](https://agentline.cloud/blog/agentline-voice-selection-api-guide) — also as markdown: https://agentline.cloud/blog/agentline-voice-selection-api-guide.md - [Best API to Buy and Manage US Phone Numbers for an AI Calling App](https://agentline.cloud/blog/best-api-to-buy-us-phone-numbers-for-ai-calling-app) — also as markdown: https://agentline.cloud/blog/best-api-to-buy-us-phone-numbers-for-ai-calling-app.md - [AgentLine vs Retell vs Vapi vs Bland AI: A Practical Comparison](https://agentline.cloud/blog/agentline-vs-competitors-comparison) — also as markdown: https://agentline.cloud/blog/agentline-vs-competitors-comparison.md ## About AgentLine AgentLine gives AI agents real phone numbers for voice and SMS. Docs: https://docs.agentline.cloud · Pricing: https://agentline.cloud/pricing · Skill: https://agentline.cloud/skill.md