> For a complete page index, fetch https://docs.synthflow.ai/llms.txt. For full documentation content, fetch https://docs.synthflow.ai/llms-full.txt.

## Agents API: STT provider and speech recognition

Create and update assistant requests now accept the speech-to-text fields from the assistant editor.

| Endpoint                                                                                                                                                             | Change                                                                                                                                                |
| :------------------------------------------------------------------------------------------------------------------------------------------------------------------- | :---------------------------------------------------------------------------------------------------------------------------------------------------- |
| [**POST /assistants**](/api-reference/platform-api/agents/create-assistant), [**PUT /assistants/\{model\_id}**](/api-reference/platform-api/agents/update-assistant) | `agent.transcriber_provider` (`deepgram`, `deepgram-nova-3`, `synthflow-stt`) and `agent.transcriber_speech_recognition` (`faster`, `high_accuracy`). |

## Call Transfer API: Human availability

Configure transfer office hours on `LIVE_TRANSFER` actions through create and update requests.

| Endpoint                                                                               | Change                                                                          |
| :------------------------------------------------------------------------------------- | :------------------------------------------------------------------------------ |
| [**POST /v2/actions**](/api-reference/platform-api/actions/create-action)              | `human_availability` (`timezone`, `schedule`, `unavailable_message`, `active`). |
| [**PUT /v2/actions/\{action\_id}**](/api-reference/platform-api/actions/update-action) | Same `human_availability` fields on update.                                     |

## Agents and Actions API: Action-assistant assignment relationships

Assistant and action detail endpoints accept optional query parameters to include related IDs. Relationship fields stay empty by default.

| Endpoint                                                                             | Query parameter      | Response field               |
| :----------------------------------------------------------------------------------- | :------------------- | :--------------------------- |
| [**GET /assistants/\{model\_id}**](/api-reference/platform-api/agents/get-assistant) | `include_actions`    | `actions` (action IDs)       |
| [**GET /actions/\{action\_id}**](/api-reference/platform-api/actions/get-action)     | `include_assistants` | `assistants` (assistant IDs) |

## Actions API: Input variable mapping

Configure how each input variable is collected per assistant attachment, so one shared action can use different variable sources on different agents. [Action placeholders and mapping](/variables#action-placeholders-and-mapping) explains the mapping options in the product UI.

| Endpoint                                                                         | Change                                                                                                                      |
| :------------------------------------------------------------------------------- | :-------------------------------------------------------------------------------------------------------------------------- |
| [**POST /actions/attach**](/api-reference/platform-api/actions/attach-action)    | Batch `items` payloads with `input_variables_mapping` per attachment. Legacy `model_id` + `actions` format still supported. |
| [**GET /actions/\{action\_id}**](/api-reference/platform-api/actions/get-action) | `input_variables.values` and `input_variables.assistants[]` with per-assistant mapping details.                             |