Query Spans
spansFind individual spans matching filter criteria within a time range.
This is a DRILL-DOWN tool. For "where are errors / latency concentrated?" start with aggregate_spans, then use this to fetch example spans for a (service, operation).
Returns spans sorted by (timestamp, spanId) descending (newest first).
Returns the span's core fields by default; pass verbose=true to include its
attributes (flattened in, plus a resource object). Long string values are capped
(maxStringChars). For raw columns or custom selection use run_sql.
Defaults: from is 1 hour before to (or before now) when omitted — set it to read further back; to is now when omitted; limit 100 (max 1000); all filters any. Common patterns:
Errored spans of an operation: statusCode="ERROR", name="http.client"
Slow spans: minDurationMs=500
Every span of a trace: traceId="..." (or use get_trace)
A span is viewed in the context of its trace. To show one to the user, call get_trace with its traceId and hand them traceUrl, which opens the trace as a waterfall in the Fixter app, rather than drawing the span yourself.
Returns: spans[], nextCursor (null on last page), queryStats, and truncationHint when the page was cut to fit the response (nextCursor then reads on from the last span shown).
Tool call template
This tool declares no required parameters. Add optional parameters from the input schema as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {},
"name": "spans"
}
}Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| to | No | End of window, ISO-8601 instant (exclusive); now when omitted | |
| from | No | Start of window, ISO-8601 instant (inclusive); 1 hour before to (or now) when omitted | |
| kind | No | Filter by kind: SERVER, CLIENT, PRODUCER, CONSUMER, INTERNAL | |
| name | No | Filter by operation/span name (e.g. 'GET /things') | |
| limit | No | Max spans, default 100, max 1000 | |
| cursor | No | Opaque cursor from a previous next_cursor | |
| service | No | Filter by service name | |
| traceId | No | Filter to a single trace id | |
| verbose | No | Return full spans incl. attributes and resource. Default false. | |
| statusCode | No | Filter by status: UNSET, OK, ERROR | |
| minDurationMs | No | Only spans at least this many milliseconds long | |
| maxStringChars | No | Max characters of any attribute string value before truncation, at most 4000. Omit to use the server default. |