Simulate a Vapi agent

Step 1: Create a Free Vapi SIP trunk

Open the Vapi dashboard → Phone Numbers.
Create Phone Number → Free Vapi SIP.
Fill in:
- SIP Identifier (used in your SIP URI)
- Label (your reference only)
- Username and Password (digest auth)
Click Import SIP URI.

Your SIP URI will match:

sip:<SIP Identifier>@sip.vapi.ai

Save username and password immediately. Vapi shows the password only once. If you lose it, delete the trunk and create a new one.

Simulation calls will not connect if this step is skipped.

Phone Numbers → click your SIP trunk.
Under Inbound Settings, set Assistant to the assistant Tuner should reach.
Save.

Issue	What to check
Calls fail to connect	Assistant linked to trunk (Step 2). Credentials match Vapi and Tuner. URI exactly `sip:identifier@sip.vapi.ai`.
Assistant silent	Assistant has a prompt and is active (not draft/paused).
Unverified in Tuner	No trailing spaces on URI or password. Verify & Save again.

Paste your SIP URI and credentials into Agent Settings → SIP Settings, click Verify & Save, and you’re ready to run simulations.

Configure your simulation mix and start a batch.

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