Local API reference
Read live targets, saved sessions, network information, and aggregated history.
Enable the Local Web / API first. The default base URL is http://127.0.0.1:8787.
All endpoints below are GET and read-only. JSON response properties use camelCase, and enum values are strings. There are no API endpoints to add targets, change settings, acknowledge events, or start/stop monitoring.
Endpoints
| Path | Response |
|---|---|
/ | Local HTML dashboard |
/api/targets | Current engine sessions with options, state, capability, health, and latest snapshot |
/api/sessions | Saved sessions with identifiers, target, destination address, start/stop dates, and sample count |
/api/interfaces | Local interface inventory |
/api/neighbors | Existing OS neighbor cache |
/api/gateway | Object with gateway, which can be null |
/api/history/{sessionId} | Aggregated samples and events for a stored session |
/api/events/{sessionId} | Stored events within a date range |
curl http://127.0.0.1:8787/api/targets
curl http://127.0.0.1:8787/api/sessions
curl http://127.0.0.1:8787/api/interfacesCopy a session id from targets or saved sessions for the history and events requests.
History query
| Parameter | Default | Accepted values |
|---|---|---|
from | One hour ago | Date/time; use ISO 8601 with a timezone |
to | Now | Date/time at or after from |
hop | 0 | 0 for destination, or 1–64 for an intermediate hop |
maxPoints | 1200 | 1–10000 |
For example, replace the illustrative session ID with your own:
curl 'http://127.0.0.1:8787/api/history/00000000-0000-0000-0000-000000000002?hop=0&from=2026-10-14T12:00:00Z&to=2026-10-14T13:00:00Z&maxPoints=1200'History returns sessionId, hop, from, to, sampleCount, errorCount, truncated, points, and events. Points are aggregated across the requested interval rather than being a raw CSV export. sampleCount sums point counts and errorCount sums local errors. The current endpoint reports truncated: false.
Events query
from defaults to 24 hours ago and to defaults to now. It returns an array of stored events, including acknowledgment information when present.
curl 'http://127.0.0.1:8787/api/events/00000000-0000-0000-0000-000000000002?from=2026-10-14T00:00:00Z&to=2026-10-15T00:00:00Z'Invalid session IDs, date ranges, or numeric parameters return 400. An unknown stored session returns 404.
Measurement semantics
Target snapshots include the actual measurement options/epoch, route changes, response kind, and transmission evidence. lossAvailable is false when no eligible attempts exist. applicationServiceAvailable is true for UDP replies or successful TCP connects, false for UDP Port Unreachable or TCP reset responses, and otherwise null.
UDP target health distinguishes NoResponse, ProbeRejected, Reachable, and Responded. ICMP/TCP health can be Healthy, Degraded, or Unreachable; the API's fixed degraded thresholds are 5% response loss, 150 ms average latency, or 30 ms jitter. These labels do not use your display colors or alert thresholds. Paused, stopped, waiting, and local-error states are reported separately.
Response loss is diagnostic
Access and lifetime
The listener binds to IPv4 loopback only. It accepts Host values 127.0.0.1 and localhost; other hosts return 400. No API authentication or cross-origin access configuration is provided. Responses use Cache-Control: no-store. The local dashboard and API require the desktop process to remain open.
If a connection fails, confirm that the listener is enabled, use the configured port and 127.0.0.1, and check for a port-in-use error in Pngr. Remote access and independent server deployment are not supported.