Function ClassifyModelError

pkg/modelerrors/modelerrors.go:581–616

ClassifyModelError classifies an error for the retry/fallback decision. If the error chain contains a *StatusError (wrapped by provider adapters), its StatusCode and RetryAfter fields are used directly — no provider-specific imports needed in the caller. Returns: - retryable=true: retry the SAM

(err error)

// deciding whether to retry (when no fallback is configured) or skip to the next
// model (when fallbacks are available).
func ClassifyModelError(err error) (retryable, rateLimited bool, retryAfter time.Duration) {
	if err == nil {
		return false, false, 0
	}

	// Context cancellation and deadline are never retryable.
	if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
		return false, false, 0
	}

	// Context overflow errors are never retryable — retrying the same oversized
	// payload will always fail.
	if IsContextOverflowError(err) {
		return false, false, 0
	}

	// Primary path: typed StatusError wrapped by provider adapters.
	var statusErr *StatusError
	if errors.As(err, &statusErr) {
		if statusErr.StatusCode == http.StatusTooManyRequests {
			return false, true, statusErr.RetryAfter
		}
		return isRetryableStatusCode(statusErr.StatusCode) || matchesTransientPattern(err), false, 0
	}

	// Fallback: providers that don't yet wrap (e.g. Bedrock), or non-provider
	// errors (network, pattern matching).
	statusCode := extractHTTPStatusCode(err)
	if statusCode == http.StatusTooManyRequests {
		return false, true, 0 // No Retry-After without StatusError
	}
	if statusCode != 0 {
		return isRetryableStatusCode(statusCode) || matchesTransientPattern(err), false, 0
	}
	return isRetryableModelError(err), false, 0
}

// FormatError returns a user-friendly error message for model errors.
// Overflow errors get a kind-specific actionable message; other errors fall