Method handleGetAttributeValues

modules/frontend/mcp_tools.go:292–329

handleGetAttributeValues handles the get-attribute-values tool

(ctx context.Context, request mcp.CallToolRequest)

// handleGetAttributeValues handles the get-attribute-values tool
func (s *MCPServer) handleGetAttributeValues(ctx context.Context, request mcp.CallToolRequest) (*mcp.CallToolResult, error) {
	metricMCPToolCalls.WithLabelValues(toolGetAttributeValues).Inc()

	name, err := request.RequireString("name")
	if err != nil {
		return mcp.NewToolResultError(err.Error()), nil
	}

	query := request.GetString("filter-query", "")
	if !traceql.IsEmptyQuery(query) {
		conditionGroups, _ := traceql.ExtractConditionGroups(query, traceql.DefaultMaxConditionGroupsPerTagQuery)
		if len(conditionGroups) == 0 {
			return mcp.NewToolResultError("filter-query invalid. It must have a single spanset filter with &&/|| conditions like { <cond> && <cond> } or { <cond> || <cond> }"), nil
		}
	}

	level.Info(s.logger).Log("msg", "getting attribute values", "name", name, "filter query", query)

	searchTagValuesReq := &tempopb.SearchTagValuesRequest{
		TagName: name,
		Query:   query,
	}

	req, err := api.BuildSearchTagValuesRequest(nil, searchTagValuesReq)
	if err != nil {
		return mcp.NewToolResultError(fmt.Sprintf("failed to build search request: %v", err)), nil
	}
	req.URL.Path = s.buildPath("/api/v2/search/tag/" + url.PathEscape(name) + "/values")

	req, ctx = injectMuxVars(ctx, req, map[string]string{api.MuxVarTagName: name})

	body, err := handleHTTP(ctx, s.frontend.SearchTagsValuesV2Handler, req)
	if err != nil {
		return mcp.NewToolResultError(err.Error()), nil
	}

	return toolResult(body, MetaTypeAttributeValues, "json", "2"), nil
}

func handleHTTP(ctx context.Context, handler http.Handler, req *http.Request) (string, error) {
	rw := newResponseBuffer()