The lango agent command group covers two surfaces:
- inspection commands such as
status,list,tools, andhooks - diagnostics commands such as
trace,graph, and trace-derived metrics
Inspection-oriented commands are documented in Agent & Memory. This page focuses on the diagnostics surface that uses bootstrap-backed trace storage.
All diagnostics commands accept --output table|json and reject unknown values before bootstrap-dependent work begins.
Human-readable and JSON output are routed through the Cobra command writer so wrappers and test harnesses can capture them directly.
List recent turn traces.
lango agent trace list [--session <key>] [--outcome <outcome>] [--limit N] [--output table|json]
Flags:
| Flag | Default | Description |
|---|---|---|
--session |
"" |
Filter by session key |
--outcome |
"" |
Filter by trace outcome |
--limit |
20 |
Maximum traces to return |
--output |
table |
Output format: table or json |
Show a detailed event timeline for one trace.
lango agent trace show <trace-id> [--output table|json]
Flags:
| Flag | Default | Description |
|---|---|---|
--output |
table |
Output format: table or json |
Show trace-derived per-agent performance metrics.
This is distinct from lango metrics agents, which reports token usage rather than trace outcomes and durations.
lango agent trace metrics [--agent <name>] [--output table|json]
Flags:
| Flag | Default | Description |
|---|---|---|
--agent |
"" |
Filter by agent name |
--output |
table |
Output format: table or json |
Show the delegation graph for a session.
lango agent graph <session-key> [--output table|json]
Flags:
| Flag | Default | Description |
|---|---|---|
--output |
table |
Output format: table or json |
trace,graph, and trace-derived metrics use bootstrap-backed storage rather than config-only inspection.lango agent trace metricslives under thetracecommand tree; it is not exposed as a root-levellango agent metricscommand.- If no diagnostics data exists, the commands render explicit empty-state output instead of failing silently.