Slomo CLI: doctor — Root-Cause Diagnosis for Issues

slomo doctor walks the recorded timeline backwards from the crash and applies heuristics to produce a structured diagnosis. Pass the issue id to diagnose.

slomo doctor REF

REF

string

required

Issue id, e.g. SM-1a2b3c4d.

$ slomo doctor SM-8b6f710a
Category              Null Reference  (95% confidence)
Occurrences           5  (5 unhandled) across 5 session(s)
Likely root cause     TypeError raised in checkout() at app.py:14.
                      Variable 'inventory' was None at the crash site.
First bad function    checkout()
First bad variable    inventory
Suggested fix         Guard against None before the failing access at app.py:14
                      — trace where the value is produced and handle the missing case.
Context just before the crash:
  13:04:52.133 sql.query   SELECT sku, qty FROM inventory WHERE sku = ?
  13:04:52.133 sql.result  0 rows, 9µs

Reading the report

Field	Meaning
Category	Automatic classification with its confidence score
Severity	Inferred severity level of the issue
Status	Current status and stability (e.g. `open / recurring`)
Occurrences	Incident count, unhandled count, affected sessions
First seen	Timestamp of the first recorded incident
Last seen	Timestamp of the most recent incident
Likely root cause	Where the exception was raised, and what the crash-site state implies
First bad function	The earliest function in the trace where the failing value appeared
First bad variable	The variable that was already wrong at the crash site
Suggested fix	A heuristic suggestion — a starting point, not gospel
Context	The SQL/HTTP/log events immediately before the crash — often the actual answer (above: the query returned 0 rows)
Related issues	Other issues with similar fingerprints and their similarity scores

The diagnosis is built from the same captured data you can inspect yourself — crash-frame locals (snapshots), spans, and the surrounding events. When the doctor’s heuristic isn’t enough, replay the same incident and rewind from the crash by hand.

Python API

CLI

Slomo CLI: doctor — Root-Cause Diagnosis for Issues

Reading the report

See also

​Reading the report

​See also

Reading the report

See also