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The programmatic path: on the Unpod side create a SIP trunk and attach your number to get a SIP endpoint + credentials; then call Ultravox’s Create Agent Call endpoint with those SIP details. Ultravox places the outbound call through your Unpod trunk. Prefer clicks? See the Dashboard guide.
Unpod Base URL: https://unpod.ai/api/v2/platform/ Every Unpod request needs Authorization: Token <your-api-key> and an Org-Handle header. See Authentication.

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Prerequisites

  • An Unpod API Token and Org-Handle, plus a number on a Bridge.
  • An Ultravox API key and an agent (note its Agent ID).

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1. Find your Unpod number

cURL
curl https://unpod.ai/api/v2/platform/telephony/numbers/ \
  -H "Authorization: Token $UNPOD_TOKEN" \
  -H "Org-Handle: $ORG_HANDLE"
Response (200)
{
  "status_code": 200,
  "message": "Telephony numbers fetched successfully.",
  "data": [
    { "id": 501, "number": "+918071539111", "state": "ASSIGNED", "active": true }
  ]
}

List Numbers reference

Full request/response schema.

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2. Create the SIP trunk

Set auth_username / auth_password - these become the SIP credentials Ultravox authenticates with when it dials into Unpod.
cURL
curl -X POST https://unpod.ai/api/v2/platform/telephony/trunks/ \
  -H "Authorization: Token $UNPOD_TOKEN" \
  -H "Org-Handle: $ORG_HANDLE" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Ultravox trunk",
    "sip_url": "sip:sip-lb1.unpod.tel",
    "auth_username": "unpod_user_501",
    "auth_password": "<choose-a-password>",
    "transport": "udp",
    "port": "5060"
  }'
Response (201)
{
  "status_code": 201,
  "message": "Trunk created successfully.",
  "data": { "id": 21, "name": "Ultravox trunk", "auth_username": "unpod_user_501", "active": true }
}

Create Trunk reference

All request fields (sip_url, auth_username, auth_password, transport, port, source_ips).

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3. Attach your number to the trunk

Map the number from step 1 (its id) to the trunk from step 2 (its id). The response returns the origin endpoint - the SIP domain Ultravox dials into.
cURL
curl -X POST https://unpod.ai/api/v2/platform/telephony/trunks/21/attach-numbers/ \
  -H "Authorization: Token $UNPOD_TOKEN" \
  -H "Org-Handle: $ORG_HANDLE" \
  -H "Content-Type: application/json" \
  -d '{ "number_ids": [501] }'
Response (201)
{
  "status_code": 201,
  "message": "Numbers mapped to trunk.",
  "data": {
    "trunk_id": 21,
    "origin_endpoint": { "ingress": "sip:sip-lb1.unpod.tel", "dids": ["+918071539111"] }
  }
}
You now have everything Ultravox needs:
  • SIP domain - host from origin_endpoint.ingress (e.g. sip-lb1.unpod.tel, drop the sip:).
  • auth_username / auth_password - the creds you set in step 2.
  • Your number (+918071539111) for caller ID.

Attach Numbers reference

Path params, request body, and the full origin-endpoint response.

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4. Place the call from Ultravox

This is Ultravox’s own API (api.ultravox.ai, X-API-Key header). Point to at your Unpod SIP domain and pass the Unpod credentials.
cURL
curl -X POST https://api.ultravox.ai/api/agents/YOUR_AGENT_ID/calls \
  -H "X-API-Key: YOUR_ULTRAVOX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "medium": {
      "sip": {
        "outgoing": {
          "to": "sip:+919999999999@sip-lb1.unpod.tel",
          "from": "+918071539111",
          "username": "unpod_user_501",
          "password": "<the-password-from-step-2>"
        }
      }
    },
    "firstSpeakerSettings": { "user": {} }
  }'
FieldValue
toDestination as sip:<number>@<your-unpod-sip-domain>
fromYour Unpod number (caller ID)
username / passwordUnpod auth_username / auth_password from step 2
firstSpeakerSettings{ "user": {} } - callee speaks first (outbound)
Ultravox returns a callId and sends the SIP INVITE through Unpod. The agent joins when the callee answers.

Ultravox Create Agent Call

Full request body + response (this is Ultravox’s API).

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5. Debug with SIP logs

If a call is rejected, pull Ultravox’s SIP logs for that callId:
cURL
curl https://api.ultravox.ai/api/calls/CALL_ID/sip/logs \
  -H "X-API-Key: YOUR_ULTRAVOX_API_KEY"

Ultravox SIP logs

SIP log fields for debugging rejected calls (this is Ultravox’s API).

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Troubleshooting

StatusMeaningFix
403Auth rejected by UnpodRe-check username / password (Unpod trunk creds from step 2)
407Proxy auth requiredEnsure username / password are in sip.outgoing
480Destination unavailableVerify the to number; confirm your Unpod number is active
401 (Unpod)Bad Unpod tokenVerify Authorization: Token … on Unpod calls

No-code version

The same flow, gathering creds in the UIs.

All platforms

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