GET /api/metrics/:chain returns JSON metrics for the node-local public profile. Its provider and method measurements describe upstream attempts; a client request can make several attempts during failover. See the metrics API for its fields, units, and nullable values.
GET /metrics exposes Prometheus text for node-local routed request counts by chain, provider, method, and outcome. It also reports local circuit state and fresh provider head lag. Request labels occupy at most 4,096 series slots; unknown methods use other, and dropped observations increment lasso_rpc_request_observations_dropped_total. Circuit and lag samples scan at most 2,048 configured routes per scrape. Missing lag is unknown, not zero.
Scrape each Core node separately and retain an instance label in Prometheus when you aggregate nodes. Restrict /metrics to your collector at the proxy or private network boundary: Core does not authenticate that endpoint, and labels can include configured provider identifiers. You can import the versioned Grafana dashboard to inspect these series.
The dashboard request tester generates real upstream traffic. Its success, error, and latency counters describe that browser’s test run. Open WebSocket connection counts do not establish that every subscription succeeded; the activity feed records confirmations and errors separately.
The request pipeline also emits [:lasso, :rpc, :request, :stop] with a millisecond duration measurement and metadata for chain, method, strategy, provider, transport, result, and failovers. This event describes routed request completion. Locally handled methods, invalid requests, and pre-dispatch failures follow other paths, so it is not a complete ingress counter. An embedding deployment can attach its own telemetry handler and export measurements to its monitoring system.
VM/system metrics are disabled by default. Set LASSO_VM_METRICS_ENABLED=true to collect and display them. Protect metrics and dashboard routes at your ingress when deployed publicly.
See the released observability reference for the event schema and metrics API for response examples.