fabro/lib
Bryan Helmkamp 14f69f50cd
Surface dropped Daytona output to the agent as a stderr line
When the driver reports an output loss on a streaming exec, the pebble
Environment adapter now appends one line to the stderr it hands back:

    [sandbox] N output frame(s), M bytes dropped by the provider

Pebble renders the result's stderr into the tool output, so the model
and the run log both see that the command's output is incomplete rather
than reading a silently shortened stream. The adapter also logs one
`warn!` with `dropped_frames`, `dropped_bytes`, and the command's first
word, bounded, so the operator can find the event without the log
carrying the command itself.

The loss is not folded into pebble's per-stream capture stats: the
dropped frames' stream is unknown and the counts are of encoded bytes,
so attributing them to stdout or stderr would be a guess. The driver's
`truncated` flags on both captures already say the counts undercount.
`ExecOutputTail` is pebble-owned and mirrored in the OpenAPI spec, so
the run events are left alone.

Tests cover the appended line with and without existing stderr, a
lossless command over the scripted double staying unchanged, the
bounded program name, and a lossy command end to end through
`Environment::exec` over a scripted sandbox whose exec facet reports a
loss (the driver's scripted double has no knob for it).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
2026-09-14 12:24:02 -06:00
..
apps Print tool calls and the transcript under fabro exec --verbose 2026-09-14 10:56:53 -06:00
components Surface dropped Daytona output to the agent as a stderr line 2026-09-14 12:24:02 -06:00
foundation Remove tests and fixtures tied to retired manifest fields 2026-09-13 08:55:55 -06:00
packages/fabro-api-client Retire legacy manifest run creation 2026-09-13 08:49:50 -06:00