***

description: Configure how an agent starts a conversation and delivers the greeting message.
title: Greeting Message Behavior
---------------------

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Agents can start conversations in different ways depending on the configured **greeting mode**. The greeting mode controls whether the agent waits for the human to speak first or delivers a greeting automatically.

## Where to find it

For **Single-Prompt** agents, the greeting message field is at the top of the [agent editor](/the-agent-editor). Type your greeting text directly into the **Greeting message** field.

![The Greeting message field in the Single-Prompt agent editor](https://files.buildwithfern.com/synthflow.docs.buildwithfern.com/855ce9423f2db61f39fd62be3496faaefb381e4de2bceb44731e8bb0b55feadd/docs/assets/screenshots/agent_editor_1.png)

For **Flow Designer** agents, the greeting is configured in the [Greeting Message node](/configure-the-greeting-message-node) — the first node in every flow.

To control how the greeting is delivered (static text, dynamically generated, or human-first), use the `greeting_message_mode` field in the [Platform API](/getting-started-with-your-api).

## greeting\_message\_mode

Defines how the agent starts the conversation and how the greeting
message is delivered.

| Mode            | Description                                                                                                   |
| --------------- | ------------------------------------------------------------------------------------------------------------- |
| `human`         | The agent waits for the human to speak first. No greeting is played automatically.                            |
| `agent_static`  | The agent immediately speaks the configured `greeting_message` once the call is established.                  |
| `agent_dynamic` | The agent dynamically generates a greeting using the agent prompt and speaks it once the call is established. |

### Example

```json
{
  "greeting_message_mode": "agent_static"
}
```

### Notes

* **`agent_static`** uses the exact text provided in
  `greeting_message`.
* **`agent_dynamic`** ignores the static `greeting_message` value and
  generates the greeting using the agent's prompt context.
* **`human`** mode is useful when the caller is expected to initiate
  the conversation (for example, inbound support calls).

***

## greeting\_message\_human\_talk\_timeout

Defines how long the agent waits for the human to speak when
`greeting_message_mode` is set to `human`.

If the caller does not speak within the configured time, the agent will
automatically start the conversation.

| Field                                 | Type    | Nullable | Example |
| ------------------------------------- | ------- | -------- | ------- |
| `greeting_message_human_talk_timeout` | integer | yes      | `3`     |

### Example

```json
{
  "greeting_message_mode": "human",
  "greeting_message_human_talk_timeout": 3
}
```

### Behavior

1. The call connects.
2. The agent waits for the human to speak.
3. If the human speaks → the agent responds normally.
4. If the timeout is reached → the agent automatically begins the
   conversation.

***

## Complete Example

Example with **agent static mode**:

```json
{
  "agent": {
    "greeting_message": "Hello! How can I help you today?",
    "greeting_message_mode": "agent_static"
  }
}
```

Example with **agent dynamic mode**:

```json
{
  "agent": {
    "greeting_message": "",
    "greeting_message_mode": "agent_dynamic"
  }
}
```

Example with **human-first mode with 3-second timeout and dynamic greeting message**:

```json
{
  "agent": {
    "greeting_message_mode": "human",
    "greeting_message_human_talk_timeout": 3
  }
}
```

Example with **human-first mode with 3-second timeout and static greeting message**:

```json
{
  "agent": {
    "greeting_message_mode": "human",
    "greeting_message_human_talk_timeout": 3,
    "greeting_message": "Hello! How can I help you today?"
  }
}
```