googleapis/mcp-toolbox · error

source is not compatible with the tool

Error message

source is not compatible with the tool

What it means

Thrown by the bigtableupdatelogicalview Tool.ValidateSource when the supplied source does not implement the tool's compatibleSource interface. The logical-view update is rejected before contacting the Bigtable admin API.

Source

Thrown at internal/tools/bigtable/bigtableupdatelogicalview/bigtableupdatelogicalview.go:96

			allParameters,
		),
	}, nil
}

var _ tools.Tool = Tool{}

type Tool struct {
	tools.BaseTool[Config]
}

func (t Tool) GetSourceName() string {
	return t.Cfg.Source
}

func (t Tool) ValidateSource(src sources.Source) error {
	_, ok := src.(compatibleSource)
	if !ok {
		return fmt.Errorf("source is not compatible with the tool")
	}
	return nil
}

func (t Tool) ToConfig() tools.ToolConfig {
	return t.Cfg
}

func (t Tool) Invoke(ctx context.Context, src sources.Source, params parameters.ParamValues, accessToken tools.AccessToken) (any, util.ToolboxError) {
	source, ok := src.(compatibleSource)
	if !ok {
		return nil, util.NewClientServerError("source used is not compatible with the tool", http.StatusInternalServerError, nil)
	}

	paramsMap := params.AsMap()

	res, err := source.UpdateLogicalView(ctx, paramsMap["instance_id"].(string), paramsMap["logical_view_id"].(string), paramsMap["query"].(string))
	if err != nil {

View on GitHub (pinned to 8cc6e09de2)

Solutions

  1. Set the tool's source to a compatible bigtable source in tools.yaml
  2. Confirm the source initializes as a Bigtable source
  3. Restart the toolbox to reload configuration
  4. Pass the correct concrete Source type satisfying compatibleSource in code

Example fix

// before (tools.yaml)
tools:
  update-logical-view:
    kind: bigtable-update-logical-view
    source: my-alloydb
// after
tools:
  update-logical-view:
    kind: bigtable-update-logical-view
    source: my-bigtable-instance
Defensive patterns

Strategy: type-guard

Validate before calling

// Check compatibility before invoking the logical-view update
if err := tool.ValidateSource(mySource); err != nil {
    return fmt.Errorf("source %s is not usable by bigtable-update-logical-view", sourceName)
}

Type guard

func isCompatibleLogicalViewSource(s sources.Source) bool {
    _, ok := s.(bigtableupdatelogicalview.CompatibleSource)
    return ok
}

Prevention

When it happens

Trigger: ValidateSource/Invoke receives a source failing the type assertion to bigtableupdatelogicalview's compatibleSource — the tool is attached to a non-Bigtable or otherwise incompatible source.

Common situations: Misconfigured tools.yaml where source points at the wrong source kind; duplicated tool blocks for different sources; programmatic tool construction with a mismatched Source.

Related errors

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/b7dc53fd2bc176d9. Report an issue: GitHub.