googleapis/mcp-toolbox · error

failed to create DataChatClient: %w

Error message

failed to create DataChatClient: %w

What it means

When the cloudgda source is not configured for client-side OAuth, Initialize creates a shared google.golang.org/api geminidataanalytics.DataChatClient with the server's Application Default Credentials. Failure to construct that client aborts source initialization with this wrapped error.

Source

Thrown at internal/sources/cloudgda/cloud_gda.go:80

	return SourceType
}

// Initialize initializes a Gemini Data Analytics Source instance.
func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
	ua, err := util.UserAgentFromContext(ctx)
	if err != nil {
		return nil, fmt.Errorf("error in User Agent retrieval: %s", err)
	}

	s := &Source{
		Config:    r,
		userAgent: ua,
	}

	if !r.UseClientOAuth {
		client, err := NewDataChatClient(ctx, option.WithUserAgent(ua))
		if err != nil {
			return nil, fmt.Errorf("failed to create DataChatClient: %w", err)
		}
		s.Client = client
	}

	return s, nil
}

var _ sources.Source = &Source{}

type Source struct {
	Config
	Client    *geminidataanalytics.DataChatClient
	userAgent string
}

func (s *Source) IsReadOnly() bool {
	return false
}

View on GitHub (pinned to 8cc6e09de2)

Solutions

1. Set up Application Default Credentials (gcloud auth application-default login or a service-account key via GOOGLE_APPLICATION_CREDENTIALS)
2. Enable the Gemini Data Analytics API on the project in Google Cloud Console
3. Set UseClientOAuth: true in the source config to use the caller's OAuth token instead of ADC
4. Check the wrapped error for quota or API-disabled details

Example fix

// before
source: my-gda
  kind: cloud-gda
  project: my-project
// after
source: my-gda
  kind: cloud-gda
  project: my-project
  useClientOAuth: true

// verify ADC before initializing
creds, err := google.FindDefaultCredentials(ctx, "https://www.googleapis.com/auth/cloud-platform")
if err != nil { return fmt.Errorf("ADC unavailable: %w", err) }
_ = creds

// Go: wrap Initialize and surface the wrapped client error
src, err := cfg.Initialize(ctx, tracer)
if err != nil {
    if strings.Contains(err.Error(), "DataChatClient") {
        return fmt.Errorf("check ADC / enable Gemini Data Analytics API: %w", err)
    }
    return err
}

When it happens

Trigger: UseClientOAuth is false (or unset) and NewDataChatClient fails — typically because ADC are absent, the Gemini Data Analytics API is not enabled on the project, or the client options are invalid.

Common situations: Running the toolbox in an environment without GOOGLE_APPLICATION_CREDENTIALS or metadata-server credentials, or a GCP project where the Cloud Gemini/Data Analytics API hasn't been enabled.

Related errors

• failed to find default credentials: %w
• failed to create per-request DataChatClient: %w
• failed to initialize dataplex client: %w
• error creating client from OAuth access token: %w
• failed to get dataplex client: %w

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/a5e2783702f8e86b. Report an issue: GitHub.