What causes "failed to get request id: %w" in BoundaryML/baml?

Unwrap the error to see the core-side reason (likely 'no http request' for failed calls)

failed to get request id

Error message

failed to get request id: %w

What it means

Thrown by llmCall.RequestId() in BAML's Go client when raw_objects.CallMethod(l, "http_request_id") fails at the FFI boundary; the core error is wrapped with %w. It means the LLM call object could not serve its associated HTTP request id, typically because the call has no linked HTTP request or the raw object handle is invalid.

Solutions

Unwrap the error to see the core-side reason (likely 'no http request' for failed calls)
Check LLMCall.HttpRequest() first; if it returns nil the call never made an HTTP request and has no request id
Only read RequestId() on completed calls with an attached HTTPRequest/HTTPResponse
Align Go bindings and BAML core versions

Example fix

id, err := llmCall.RequestId()
if err != nil {
    // failed calls may have no http_request_id
    if _, hErr := llmCall.HttpRequest(); hErr != nil {
        return "", fmt.Errorf("call has no http request: %w", err)
    }
    return "", err
}

Defensive patterns

Strategy: validation

Validate before calling

if _, err := llmCall.HttpRequest(); err != nil {
    // no associated http request; skip RequestId()
}

Try / catch

id, err := llmCall.RequestId()
if err != nil {
    log.Printf("no request id for this call (possibly a failed call): %v", err)
    id = ""
}

Prevention

Verify the call has an HTTPRequest before reading its request id
Only inspect request ids on completed LLM calls
Keep baml engine and Go bindings on matching versions

When it happens

Trigger: Calling LLMCall.RequestId() on an llmCall raw object for which the core cannot resolve http_request_id — e.g. calls that never issued an HTTP request (client-side failures), stale pointers, or bindings/core version drift.

Common situations: Inspecting failed or synthetic LLM calls in BAML event logs that have no underlying HTTP request; accessing call metadata after runtime teardown; version-mismatched installations.

Understand the failure class

Background: "API request failed": what wrapped HTTP errors from external APIs mean and how to find the real cause — this error's family across 29 libraries.

Related errors

AI-assisted analysis of BoundaryML/baml@bd85ce9dee (2026-09-12). Data as JSON: /api/errors/8dc3107bba7812e4. Report an issue: GitHub.

Appendix: source

Thrown at engine/language_client_go/pkg/rawobjects_llm_call.go:30

	*raw_objects.RawObject
}

func newLLMCall(ptr int64, rt unsafe.Pointer) LLMCall {
	return &llmCall{raw_objects.FromPointer(ptr, rt)}
}

func (l *llmCall) ObjectType() cffi.BamlObjectType {
	return cffi.BamlObjectType_OBJECT_LLM_CALL
}

func (l *llmCall) pointer() int64 {
	return l.RawObject.Pointer()
}

func (l *llmCall) RequestId() (string, error) {
	result, err := raw_objects.CallMethod(l, "http_request_id", nil)
	if err != nil {
		return "", fmt.Errorf("failed to get request id: %w", err)
	}

	return result.(string), nil
}

func (l *llmCall) ClientName() (string, error) {
	result, err := raw_objects.CallMethod(l, "client_name", nil)
	if err != nil {
		return "", fmt.Errorf("failed to get client name: %w", err)
	}

	name, ok := result.(string)
	if !ok {
		return "", fmt.Errorf("unexpected type for client name: %T", result)
	}

	return name, nil
}

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