How do I trigger and handle function calls for REST API database interactions using the Assistants API?

Below is an outline of how the process works:

1. Run Creation and Pending Status:
   When you first initiate a run, it enters a pending status. Once processed, if your assistant needs additional tool outputs, the run status will change to requires_action and include the details of which functions (or tool calls) need to be executed.

2. Handling requires_action:
   When you detect that the run has changed to requires_action, you should extract the list of tool calls from the required_action payload. For each tool call (which contains the function name and its associated arguments), your system should execute the corresponding function (in your case, making a REST API call to your database).

3. Submitting Tool Outputs:
   After all the tool executions are completed, you need to submit all outputs in a single request to the /v1/threads/{thread_id}/runs/{run_id}/submit_tool_outputs endpoint. The submission must occur before the run expires (10 minutes after creation).

4. Polling or Event-Driven Approach:
   While you could periodically check the run status to detect the requires_action state, an event-driven approach (or webhook, if available) is often more efficient. In many implementations, you poll the run status at regular intervals until you see requires_action, then carry out the necessary function calls immediately.

Below is a simplified pseudo-code example in JavaScript to illustrate the process:

JAVASCRIPTCopied
async function pollRunStatus(threadId, runId) {
  while (true) {
    const run = await fetchRun(threadId, runId); // your function to GET run status
    if (run.status === "requires_action") {
      // Extract tool_calls from run.required_action
      const toolCalls = run.required_action.submit_tool_outputs.tool_calls;
      
      // Execute all function calls
      const outputs = await Promise.all(toolCalls.map(async (call) => {
        // Call your function corresponding to the tool call
        // For example, getDbData is your handler for REST API calls to your DB
        return await getDbData(call.function.name, call.function.arguments);
      }));

      // Submit all outputs back at once to resume run execution
      await submitToolOutputs(threadId, runId, outputs);
      
      break; // Exit the polling loop after submission
    }
    
    // Wait a short time before polling again (e.g., 1-2 seconds)
    await new Promise(resolve => setTimeout(resolve, 2000));
  }
}

Key points:

• Polling vs Event-driven:
  You may use either periodic polling or an event-driven method if available. The key is to trigger your function calls as soon as the run signals it needs tool outputs.

• Single Request Submission:
  Remember that the assistant requires all tool outputs to be submitted in one combined request using the submission endpoint.

• Runtime Window:
  Make sure to complete the tool calls and submission before the 10-minute expiration.

This approach ensures that once a run indicates requires_action, your service can promptly execute the necessary REST API calls to your database and submit the outputs back to the run.