Paste a log or open a file and this tool understands it: it detects the format, groups lines into events (a 40-line stack trace is ONE event, not 40), mines the patterns that repeat, points at the root cause of exceptions, and shrinks it so you can paste it into an AI without spending a fortune in tokens. All in your browser: the log never leaves your machine.
If you filter by ERROR line by line, you keep the header of the failure and lose the stack trace, which is exactly what you were going to read. Here the continuations (at …, Caused by:, File "…", line N) are attached to their event before anything filters, counts or shrinks.
"connected to 10.0.0.1" and "connected to 10.0.0.7" are the same message. Grouping them turns a million-line log into two hundred things a person can read. Out of that come the error rate per pattern, what shows up only once (usually what you were after), and the comparison between two runs.
Trims the log to a token budget you set, keeping the errors with their stack trace, what happened just before, and the exceptional bits; repeated lines are summarised with their count. Tokens are counted with the model's real tokenizer, not an estimate. And you can mask the secrets before copying.
Checks whether your log is well written: passwords printed out, the same line forty thousand times, timestamps without a timezone (which make it impossible to correlate two machines), everything at the same level, or no identifier to follow a request with.
There is no live tailing ("tail -f"): with no server there is nothing to follow. Of a very large file a window is analysed (beginning or end) and you are told which one — to walk through hundreds of GB there is the Huge file viewer.