how can we resume Human-in-loop using API?

[shrutivermanaf]

I am trying to resume human-in-loop from .NET client using API, but its not giving 400 with unclear error. "status": "FAILED_PRECONDITION"

curl -X POST "https://us-central1-aiplatform.googleapis.com/v1/projects/ai-gcp/locations/us-central1/reasoningEngines/121093008882072:streamQuery?alt=sse"
-H "Authorization: Bearer YOUR_GOOGLE_ACCESS_TOKEN"
-H "Accept: text/event-stream"
-H "Content-Type: application/json"
-d '{
"classMethod":"async_stream_query",
"input":{
"session_id":"292676045260193792",
"message":{
"author":"user",
"content":{
"role":"user",
"parts":[
{
"functionResponse":{
"id":"f84ab8a3-27c7-49ac-b9d1-3364361cfca4", // this my interruptId
"name":"adk_request_input",
"response":{"result":"approve"}
}
}
]
}
}
}
}'

Please advise.

[cookesan]

The shape is close, but for ADK resume the function response has to be treated as the resume message for the same interrupted invocation, not as a normal new user message.

The current RequestInput docs say the client resumes by sending a FunctionResponse named adk_request_input, with the id matching the interrupt_id, and with the payload inside functionResponse.response. In the runner, function-response parts are extracted by id into resume_inputs; a message that contains function responses must not also contain text, and ADK resolves the invocation from the matching function-call event if one is not supplied.

So I would check this minimal message shape first:

{
  "role": "user",
  "parts": [
    {
      "functionResponse": {
        "id": "the exact interrupt_id from the RequestInput event",
        "name": "adk_request_input",
        "response": { "result": "approve" }
      }
    }
  ]
}

Use the same session_id that contains the original interrupt event, do not include any text part in the same message, and if the service exposes an invocation id from the interrupted run, pass that instead of relying on inference. If any of those ids do not match the event history, FAILED_PRECONDITION is the kind of failure I would expect.