jaegertracing/jaeger · error

invalid end_time: %w

Error message

invalid end_time: %w

What it means

The Jaeger MCP get_dependencies tool handler parses the optional end_time field of GetDependenciesInput using parseDependencyTime (falling back to time.Now() when empty). If the provided value is present but cannot be parsed as a valid timestamp, the handler wraps the underlying parse error with "invalid end_time" so the MCP caller knows which field was bad. It is a request-validation error, not a storage failure.

Source

Thrown at cmd/jaeger/internal/extension/jaegerquery/internal/mcptools/internal/handlers/get_dependencies.go:47

// NewGetDependenciesHandler creates a new get_service_dependencies handler.
func NewGetDependenciesHandler(
	queryService *querysvc.QueryService,
) mcp.ToolHandlerFor[types.GetDependenciesInput, types.GetDependenciesOutput] {
	h := &getDependenciesHandler{
		queryService: queryService,
	}
	return h.handle
}

func (h *getDependenciesHandler) handle(
	ctx context.Context,
	_ *mcp.CallToolRequest,
	input types.GetDependenciesInput,
) (*mcp.CallToolResult, types.GetDependenciesOutput, error) {
	endTime, err := parseDependencyTime(input.EndTime, time.Now())
	if err != nil {
		return nil, types.GetDependenciesOutput{}, fmt.Errorf("invalid end_time: %w", err)
	}

	defaultStart := endTime.Add(-24 * time.Hour)
	startTime, err := parseDependencyTime(input.StartTime, defaultStart)
	if err != nil {
		return nil, types.GetDependenciesOutput{}, fmt.Errorf("invalid start_time: %w", err)
	}

	if !startTime.Before(endTime) {
		return nil, types.GetDependenciesOutput{}, errors.New("start_time must be before end_time")
	}

	lookback := endTime.Sub(startTime)
	deps, err := h.queryService.GetDependencies(ctx, endTime, lookback)
	if err != nil {
		return nil, types.GetDependenciesOutput{}, fmt.Errorf("failed to get dependencies: %w", err)
	}

View on GitHub (pinned to 806f444784)

Solutions

1. Pass end_time as an RFC3339/UTC timestamp, e.g. "2026-08-31T10:00:00Z".
2. Omit end_time entirely to let the handler default to time.Now().
3. Validate/format the timestamp client-side before calling the tool.
4. Read the wrapped %w error to see exactly which parse step failed.

Example fix

// before
{"tool":"get_dependencies","args":{"end_time":"now-1h"}}
// after
{"tool":"get_dependencies","args":{"end_time":"2026-08-31T09:00:00Z"}}

func validEndTime(s string) bool {
	if s == "" { return true } // defaults to time.Now()
	_, err := time.Parse(time.RFC3339, s)
	return err == nil
}

func isRFC3339(s string) bool {
	_, err := time.Parse(time.RFC3339, s)
	return err == nil
}

out, _, err := handler.Handle(ctx, req, input)
if err != nil && strings.HasPrefix(err.Error(), "invalid end_time") {
	input.EndTime = time.Now().UTC().Format(time.RFC3339)
	out, _, err = handler.Handle(ctx, req, input)
}

When it happens

Trigger: Calling the get_dependencies MCP tool with input.EndTime set to a non-timestamp string (e.g. "now", "2024-13-45", "yesterday"), or a format parseDependencyTime does not accept, such as a bare date without time or an RFC3339 string with the wrong timezone syntax.

Common situations: LLM clients or scripts filling EndTime with human-friendly phrases instead of RFC3339 timestamps; copy-pasted timestamps with missing 'T' or 'Z'; locale-formatted dates from spreadsheets or UIs; time in local format like "08/31/2026 10:00".

Related errors

• invalid start_time: %w
• trace_id is required
• start_time must be before end_time
• trace_id is required
• span_ids is required and must not be empty

AI-assisted analysis of jaegertracing/jaeger@806f444784 (2026-09-01). Data as JSON: /api/errors/753545ed9b09d40a. Report an issue: GitHub.