Flow <NO_RESPONSE_REQUIRED/> still results in spoken output — ToolInvoke/ToolResult IDs confirmed (Session: f744c80a-842a-4dc0-8c15-0461925a79ef)

[Navdeep-Dahiya]

Hello Speechmatics Support Team,

We’re integrating Speechmatics Flow Voice AI function calling and are troubleshooting <NO_RESPONSE_REQUIRED/> behavior.

Session ID:
f744c80a-842a-4dc0-8c15-0461925a79ef

We are correctly sending <NO_RESPONSE_REQUIRED/> in the ToolResult content field, and we have confirmed that the ToolResult id matches the ToolInvoke id.

Relevant logs (sanitized):

1. ToolInvoke received (includes the ToolInvoke payload with id):
   {
   "message": "ToolInvoke",
   "id": "call_kg73tvj6_8yp9x",
   "type": "function",
   "function": {
   "name": "identify_intent",
   "arguments": { "intent": "inspection" }
   }
   }

Log line:
ToolInvoke received: identify_intent with {'intent': 'inspection'} and {'message': 'ToolInvoke', 'id': 'call_kg73tvj6_8yp9x', 'type': 'function', 'function': {'name': 'identify_intent', 'arguments': {'intent': 'inspection'}}}

2. ToolResult sent (ToolResult id matches ToolInvoke id and content includes NO_RESPONSE_REQUIRED):
   {
   "message": "ToolResult",
   "id": "call_kg73tvj6_8yp9x",
   "status": "ok",
   "content": "<NO_RESPONSE_REQUIRED/>"
   }

Log line:
ToolResult sent: {'message': 'ToolResult', 'id': 'call_kg73tvj6_8yp9x', 'status': 'ok', 'content': '<NO_RESPONSE_REQUIRED/>'}

3. Our function flow returns:
   { "status": "ok", "content": "<NO_RESPONSE_REQUIRED/>" }

But it still plays a message after the tool call.

Thanks for your help.

[Navdeep-Dahiya]

Logs attached here:

comm-server-1 | 2026-02-16 13:54:05,372 INFO sqlalchemy.engine.Engine [generated in 0.00015s] (7, 'CA600736dff62724a3e3ab5e74de56d79e')
comm-server-1 | 2026-02-16 13:54:05,373 INFO sqlalchemy.engine.Engine COMMIT
comm-server-1 | 2026-02-16 13:54:05,377 [INFO] Response: 200 http://up-filly-roughly.ngrok-free.app/recording-callback
comm-server-1 | INFO: 172.19.0.4:59098 - "POST /recording-callback HTTP/1.1" 200 OK
comm-server-1 | [PRINT] 🤖 ResponseCompleted: The inspectors scheduling team is currently helping other customers, but I can collect some quick information to help get you started.
comm-server-1 | [PRINT] 🤖 ResponseCompleted: Are you calling in regards to needing a quote or new inspection setup?
comm-server-1 | [PRINT] 🗣️ Transcript: Yeah,
comm-server-1 | [PRINT] 🗣️ Transcript: I
comm-server-1 | [PRINT] 🗣️ Transcript: need
comm-server-1 | [PRINT] 🗣️ Transcript: quotation
comm-server-1 | [WEBSOCKET] process_function_call: 2
comm-server-1 | 2026-02-16 13:54:23,886 [INFO] [call_sid=CA600736dff62724a3e3ab5e74de56d79e] ToolInvoke received: identify_intent with {'intent': 'quotation'}
comm-server-1 | 2026-02-16 13:54:23,887 [INFO] [call_sid=CA600736dff62724a3e3ab5e74de56d79e] process_function_call: identify_intent with {'intent': 'quotation'}
comm-server-1 | [DBHandler] Successfully wrote 1 logs to DB.
comm-server-1 | 2026-02-16 13:54:23,947 INFO sqlalchemy.engine.Engine BEGIN (implicit)
comm-server-1 | 2026-02-16 13:54:23,948 INFO sqlalchemy.engine.Engine SELECT template.execution_schema
comm-server-1 | FROM template
comm-server-1 | WHERE template.id = %s
comm-server-1 | 2026-02-16 13:54:23,948 INFO sqlalchemy.engine.Engine [generated in 0.00022s] (58,)
comm-server-1 | 2026-02-16 13:54:23,949 INFO sqlalchemy.engine.Engine ROLLBACK
comm-server-1 | 2026-02-16 13:54:23,970 [INFO] [FLOW] Variable substitution: intent = 'quotation'
comm-server-1 | 2026-02-16 13:54:23,970 [INFO] [CONDITION] Evaluating: quotation == faqs (types: <class 'str'>, <class 'str'>)
comm-server-1 | 2026-02-16 13:54:23,970 [INFO] [CONDITION] Result: False
comm-server-1 | 2026-02-16 13:54:23,970 [INFO] [FLOW] Variable substitution: intent = 'quotation'
comm-server-1 | 2026-02-16 13:54:23,970 [INFO] [CONDITION] Evaluating: quotation == unknown (types: <class 'str'>, <class 'str'>)
comm-server-1 | 2026-02-16 13:54:23,971 [INFO] [CONDITION] Result: False
comm-server-1 | 2026-02-16 13:54:23,971 [INFO] [FLOW] Variable substitution: intent = 'quotation'
comm-server-1 | 2026-02-16 13:54:23,972 [INFO] [FLOW] Variable substitution: call_sid = 'CA600736dff62724a3e3ab5e74de56d79e'
comm-server-1 | 2026-02-16 13:54:23,973 INFO sqlalchemy.engine.Engine BEGIN (implicit)
comm-server-1 | 2026-02-16 13:54:23,974 INFO sqlalchemy.engine.Engine UPDATE call SET call_intent=%s, updated_at=%s WHERE call.call_sid = %s
comm-server-1 | 2026-02-16 13:54:23,974 INFO sqlalchemy.engine.Engine [generated in 0.00015s] ('quotation', datetime.datetime(2026, 2, 16, 13, 54, 23, 972569), 'CA600736dff62724a3e3ab5e74de56d79e')
comm-server-1 | 2026-02-16 13:54:23,974 INFO sqlalchemy.engine.Engine COMMIT
comm-server-1 | 2026-02-16 13:54:23,979 [INFO] [FLOW] Variable substitution: data.rowcount = '1'
comm-server-1 | 2026-02-16 13:54:23,979 [INFO] [CONDITION] Evaluating: 1 exists quotation (types: <class 'str'>, <class 'str'>)
comm-server-1 | 2026-02-16 13:54:23,980 [INFO] [CONDITION] Result: True
comm-server-1 | 2026-02-16 13:54:23,980 [INFO] [call_sid=CA600736dff62724a3e3ab5e74de56d79e] process_function_call result: {'status': 'ok', 'content': '<NO_RESPONSE_REQUIRED/>', 'message': 'ToolResult'}
comm-server-1 | 2026-02-16 13:54:23,980 [INFO] [call_sid=CA600736dff62724a3e3ab5e74de56d79e] ToolResult sent: {'message': 'ToolResult', 'id': 'call_znld2bmi_izafr', 'status': 'ok', 'content': '<NO_RESPONSE_REQUIRED/>'}
comm-server-1 | [PRINT] 🤖 ResponseCompleted: Let me get that started for you.
comm-server-1 | [DBHandler] Successfully wrote 14 logs to DB.
comm-server-1 | [PRINT] 🗣️ Transcript: Okay
comm-server-1 | [PRINT] 🤖 ResponseCompleted: May I have your name, please?