Start Call
You can use Start Call node to Start the call and configure how Agent greets the user when the conversation starts.
You should have only one Start Call node per Voice Agent.
Start Call is the entry point for every conversation. It fires the moment a call connects and controls the first thing your agent says. Every workflow must have exactly one.
When it runs
Start Call executes before any Agent Node. No other node can precede it in the call flow.
After Start Call completes, the conversation moves to the next node - typically your first Agent Node. If the caller hangs up immediately or reaches a wrong-number condition, Start Call can route directly to End Call instead.
Fields
Name
Short identifier shown in the canvas and call logs. Has no runtime effect on what the agent says.
Greeting Type
Whether the greeting is spoken via TTS from text or played from a pre-recorded audio file. Defaults to "Text (TTS)".
Greeting Text
Optional fixed line spoken via TTS the moment the call connects, before the AI's conversational turn begins. Supports {{template_variables}}. Leave empty to skip the greeting and let the Prompt handle the opening.
We recommend setting one. It is the fastest possible opening — and a greeting written without variables is prepared ahead of time, so the caller hears it the instant they pick up.
Hello, thanks for calling Apex Recovery Solutions. How can I help today?A greeting can include variables when you want to address the caller by name. The wording then changes on every call, so it is generated fresh each time rather than prepared in advance:
Hi {{initial_context.debtor_name}}, this is Alex from Apex Recovery Solutions.See Pre-recorded Audio to use a recording file instead of TTS text.
Prompt (required)
System instructions for the AI's opening conversational turn. Supports {{initial_context.field_name}} and variables from Pre-Call Data Fetch.
Greeting Text and Prompt open the call in different ways, and only one of them speaks first:
- With a Greeting Text, the agent speaks your exact words, then uses the Prompt to handle whatever the caller says next.
- Without one, there is no fixed opening line — the agent uses the Prompt to compose its own, so the wording differs from call to call and the caller waits for it to be generated.
For example:
After greeting the caller, confirm you are speaking with
{{initial_context.debtor_name}}. If they confirm, move to Debt Disclosure.
If they say wrong number, move to End Call.If a variable referenced in Greeting Text or Prompt is missing from the API request payload, the agent speaks the raw placeholder out loud - for example, "Hi {{initial_context.debtor_name}}" - instead of the caller's name. Test with a complete payload before publishing.
Allow Interruption
When on, the caller can interrupt the agent mid-utterance. Off by default on Start Call.
Add Global Prompt
When on and a Global Node exists, the Global Prompt is prepended to this node's Prompt at runtime. On by default.
Delayed Start
When on, the agent waits before speaking after the call connects. Useful for outbound calls where the called party needs a moment to settle. Duration can be set between 0.1 and 10 seconds.
Enable Variable Extraction
When on, an LLM extraction pass runs after this node's turn to capture structured data from the conversation into gathered_context.
Tools
Functions the agent can call during the opening turn. Add via the "HTTP & Tools" tab (HTTP API and built-in tools) or the "MCP" tab (MCP server tools).
Knowledge Base Documents
Documents the agent can reference during this step. Attach via "Manage Documents."
Pre-Call Data Fetch
When on, Talkr makes a POST request to an external API before the call starts and merges the JSON response into the call context as template variables.
Outgoing edges
Start Call can have multiple outgoing edges, each with a user-defined label and a condition written in plain language. The LLM reads the conversation and picks the edge whose condition best matches.
Each edge needs two things:
- Label: a short name shown on the canvas (you define this)
- Condition: the instruction that tells the LLM when to take this edge
A typical Start Call has two edges:
Label: "caller confirmed"
Condition: "The caller confirmed they are the right person and are ready to continue."
Label: "wrong number"
Condition: "The caller says this is the wrong number, asks not to be called, or refuses to confirm their identity."You can add more edges if the opening turn needs to branch further.
Condition every Start Call edge on something the caller says or does. A condition that is already true when the call connects — like "the call has started" or "the greeting is finished" — is met before the agent has spoken, so the agent skips its greeting and the caller's first words land mid-flow.
Write "The caller says which service they want", not "The greeting is complete."
Common mistakes
Leaving Greeting Text empty with no Prompt. If both Greeting Text and Prompt are empty, the agent says nothing at the start of the call. The caller hears silence.
Confusing Node Name with the agent's spoken name. Node Name is a canvas label for your own reference. The name the agent introduces itself as comes from the Greeting Text or Prompt content, or the persona you define in the Global Node.
Adding a second Start Call node. Each workflow has one entry point. A second Start Call node will throw an error.
Writing a Start Call edge condition that does not wait for the caller. The agent transitions out of Start Call the moment the call connects, so its greeting never gets a turn and the conversation opens partway through. See the warning under Outgoing edges.