googleapis/mcp-toolbox · error

%s path cannot be empty or contain only slashes

Error message

%s path cannot be empty or contain only slashes

What it means

Guard in the shared Firestore path validator: splitting the path on '/' produced no usable segments, i.e. the path is only slashes (e.g. '/' or '///').

Source

Thrown at internal/tools/firestore/util/validator.go:75

	if path == "" {
		return fmt.Errorf("%s path cannot be empty", pathTypeName)
	}

	// Check if it's an absolute path
	if absolutePathRegex.MatchString(path) {
		example := "users/userId"
		if pathType == CollectionPath {
			example = "users"
		}
		return fmt.Errorf("path must be relative (e.g., '%s'), not absolute (matching pattern: ^projects/[^/]+/databases/[^/]+/documents/)", example)
	}

	// Split the path using strings.Split to preserve empty segments
	segments := strings.Split(path, "/")

	// Check for empty result
	if len(segments) == 0 {
		return fmt.Errorf("%s path cannot be empty or contain only slashes", pathTypeName)
	}

	// Check segment count based on path type
	segmentCount := len(segments)
	if pathType == CollectionPath && segmentCount%2 == 0 {
		// Collection paths must have an odd number of segments
		return fmt.Errorf("invalid collection path: must have an odd number of segments (e.g., 'collection' or 'collection/doc/subcollection'), got %d segments", segmentCount)
	} else if pathType == DocumentPath && segmentCount%2 != 0 {
		// Document paths must have an even number of segments
		return fmt.Errorf("invalid document path: must have an even number of segments (e.g., 'collection/doc'), got %d segments", segmentCount)
	}

	// Validate each segment
	for i, segment := range segments {
		isCollectionSegment := (i % 2) == 0
		if err := validateSegment(segment, isCollectionSegment); err != nil {
			return fmt.Errorf("invalid segment at position %d (%s): %w", i+1, segment, err)
		}

View on GitHub (pinned to 8cc6e09de2)

Solutions

1. Remove leading/trailing and duplicate slashes
2. Send a path made of real segment names, e.g. 'users/alice'

When it happens

Trigger: Thrown at internal/tools/firestore/util/validator.go:75 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/c16a706d58fa04d7. Report an issue: GitHub.