Inline calls

POST /calls/inline takes the whole agent configuration in the request body. Nothing is stored, nothing is reused. Use it when the persona is decided at call time.

When this is the right choice

Per-user personas — the prompt is assembled from that user’s data
Generated agents — your product builds the configuration on the fly
Testing — try a prompt without creating a record you then have to clean up
Stateless architectures — you hold the config, we hold nothing

If the same configuration is used more than a handful of times, create a real agent instead — you get version history, tool assignment, a phone number, and the dashboard.

Creating one

curl -X POST "https://api.omnia-voice.com/api/v1/calls/inline" \
  -H "X-API-Key: $OMNIA_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "systemPrompt": "You are a concise support agent for Northside Clinic.",
    "voice": "Mark",
    "language": "en",
    "model": "llama",
    "temperature": 0,
    "firstSpeaker": "agent",
    "greeting": "Northside Clinic, how can I help?",
    "recordingEnabled": true
  }'

Required: systemPrompt, voice, language. The response carries websocketUrl, exactly as /calls/create does.

Every option

Field	Notes
`systemPrompt` · `voice` · `language`	Required
`model`	`gemma` · `llama` (default) · `glm`
`temperature`	0–1, default 0
`greeting`	Appended as the opening line when the agent speaks first
`firstSpeaker`	`agent` (default) · `user`
`interruptible`	First message only. Default `false`
`maxDuration`	60–7200 seconds, default 3000
`inactivityTimeout`	10–300 seconds
`inactivityAction`	`hang_up` · `prompt`
`recordingEnabled`	Default `true`
`connectionType`	`twilio` (default) · `telnyx` · `plivo` · `websocket` · `webrtc`
`websocket`	Sample rates, codec, buffering — see Calls
`selectedTools`	See below
`metadata`	Arbitrary values on the call record

systemPrompt here is the whole prompt. There is no basePrompt / context / customInstructions layering — that assembly belongs to saved agents. See Writing agent prompts for what the layered version produces, if you want to reproduce its structure by hand.

From the SDK

joinCall takes inline options directly:

const session = new OmniaSession({ apiKey: KEY });

await session.joinCall({
  systemPrompt: buildPromptFor(user),
  voice: "Mark",
  language: user.locale,
  firstSpeaker: "agent",
});

Tools

Inline calls accept selectedTools in the request. Each entry references one of three things, and exactly one of them:

Field	Meaning
`toolId`	A tool already saved in your workspace
`toolName`	A system tool, e.g. `hangUp`
`temporaryTool`	A full tool definition, defined inline for this call only

{
  "systemPrompt": "…",
  "voice": "Mark",
  "language": "en",
  "selectedTools": [
    { "toolId": "tl_abc123" },
    { "toolName": "hangUp" },
    {
      "temporaryTool": {
        "modelToolName": "checkStock",
        "description": "Check whether an item is in stock. Use when the caller asks about availability.",
        "dynamicParameters": [
          {
            "name": "sku",
            "location": "PARAMETER_LOCATION_QUERY",
            "schema": { "type": "string", "description": "The item SKU" },
            "required": true
          }
        ],
        "http": {
          "baseUrlPattern": "https://api.yourcompany.com/stock",
          "httpMethod": "GET"
        }
      }
    }
  ]
}

Setting more than one of toolId, toolName, or temporaryTool on the same entry is rejected with 400. Pick one per entry.

What you give up

	Saved agent	Inline
Version history	✅	❌
Phone number	✅	❌
Dashboard visibility	✅	❌
Corpora / knowledge	✅	❌
Config stored	✅	❌ — you own it

Calls themselves are still recorded and billed identically, and still appear in GET /calls.

Saved agents

When configuration should persist.

Tools

What temporaryTool definitions look like.

Get started

Core concepts

Tools

Telephony

Apps & SDKs

Guides

Examples

Speech to text

Help

When this is the right choice

Creating one

Every option

From the SDK

Tools

What you give up

Saved agents

Tools

​When this is the right choice

​Creating one

​Every option

​From the SDK

​Tools

​What you give up

Saved agents

Tools

When this is the right choice

Creating one

Every option

From the SDK

Tools

What you give up