googleapis/mcp-toolbox · error

missing 'type' field or it is not a string

Error message

missing 'type' field or it is not a string

What it means

Error "missing 'type' field or it is not a string" thrown in googleapis/mcp-toolbox.

Source

Thrown at internal/server/config.go:374

		}
		for name, gc := range toolsetGroups {
			if _, shadowed := groupConfigs[name]; shadowed {
				if l, err := util.LoggerFromContext(ctx); err == nil {
					l.WarnContext(ctx, fmt.Sprintf("group %q shadows a toolset of the same name; using the group definition", name))
				}
				continue
			}
			groupConfigs[name] = gc
		}
	}

	return sourceConfigs, authServiceConfigs, embeddingModelConfigs, toolConfigs, promptConfigs, groupConfigs, nil
}

func UnmarshalYAMLSourceConfig(ctx context.Context, name string, r map[string]any) (sources.SourceConfig, error) {
	resourceType, ok := r["type"].(string)
	if !ok {
		return nil, fmt.Errorf("missing 'type' field or it is not a string")
	}
	dec, err := util.NewStrictDecoder(r)
	if err != nil {
		return nil, fmt.Errorf("error creating decoder: %w", err)
	}
	sourceConfig, err := sources.DecodeConfig(ctx, resourceType, name, dec)
	if err != nil {
		return nil, err
	}
	return sourceConfig, nil
}

func UnmarshalYAMLAuthServiceConfig(ctx context.Context, name string, r map[string]any) (auth.AuthServiceConfig, error) {
	resourceType, ok := r["type"].(string)
	if !ok {
		return nil, fmt.Errorf("missing 'type' field or it is not a string")
	}
	dec, err := util.NewStrictDecoder(r)

View on GitHub (pinned to 8cc6e09de2)

When it happens

Trigger: Thrown at internal/server/config.go:374 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/2eaf67e3595f9bce. Report an issue: GitHub.