fix(telemetry): histogram buckets from OTel standard to MCP standards

internal/telemetry/telemetry.go

@@ -154,6 +154,45 @@ func newMeterProvider(ctx context.Context, r *resource.Resource, telemetryOTLP s
 		metricOpts = append(metricOpts, metric.WithReader(metric.NewPeriodicReader(gcpExporter)))
 	}
 
+	// Configure custom histogram bucket boundaries for duration metrics
+	// These boundaries follow the OpenTelemetry semantic conventions recommendation:
+	// https://opentelemetry.io/docs/specs/semconv/general/metrics/#instrument-advice
+	durationBuckets := []float64{0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 30, 60, 120, 300}
+
+	// Create views for duration histograms
+	operationDurationView := metric.NewView(
+		metric.Instrument{Name: "mcp.server.operation.duration"},
+		metric.Stream{
+			Aggregation: metric.AggregationExplicitBucketHistogram{
+				Boundaries: durationBuckets,
+			},
+		},
+	)
+
+	sessionDurationView := metric.NewView(
+		metric.Instrument{Name: "mcp.server.session.duration"},
+		metric.Stream{
+			Aggregation: metric.AggregationExplicitBucketHistogram{
+				Boundaries: durationBuckets,
+			},
+		},
+	)
+
+	toolExecutionDurationView := metric.NewView(
+		metric.Instrument{Name: "toolbox.tool.execution.duration"},
+		metric.Stream{
+			Aggregation: metric.AggregationExplicitBucketHistogram{
+				Boundaries: durationBuckets,
+			},
+		},
+	)
+
+	metricOpts = append(metricOpts,
+		metric.WithView(operationDurationView),
+		metric.WithView(sessionDurationView),
+		metric.WithView(toolExecutionDurationView),
+	)
+
 	meterProvider := metric.NewMeterProvider(metricOpts...)
 	return meterProvider, nil
 }