---
model: openai/gpt-5.6-sol
service: opencode
session: 76c5d31c-5a2f-4503-9b16-410ee7f4fab3
timestamp: 2026-08-20T14:38:50Z
git_ref: 559fd0f1
scope: code
substantive: true
raw_file: 20260820T143845Z_559fd0f1_prompt_io.raw.md
---

## Prompt

Continue preparing PR #481 after the latest fix was pushed. Follow CI and
proceed with clear next steps toward a green landing candidate.

## Response summary

Traced the remaining macOS UDS failure to cancellation racing transport
teardown inside the shielded framed-send path. Preserve pending cancellation
over a transport error caused by concurrent teardown, and add a deterministic
regression for that ordering. A follow-up A/B run showed the corrected
cancellation precedence changes which nested debugger intermediary is
rendered as the immediate source versus relay, so retain coverage for both
actor levels without pinning those racy roles. The adjusted UDS node passes
three consecutive runs, and both debugger/tooling transport suites pass with
39 passed and 6 skipped.

## Files changed

- `tractor/ipc/_transport.py` - deliver pending cancellation before
  translating a shielded send's transport error.
- `tests/ipc/test_each_tpt.py` - reproduce cancellation followed by local
  stream closure during shielded frame publication.
- `tests/devx/test_debugger.py` - accept either valid source/relay role for
  each nested intermediary while retaining the actor and error assertions.

## Human edits

The human pushed the preceding fix, ran the proposed verification plan, and
reported a repeated UDS debugger failure. That report prompted the A/B
comparison and role-insensitive assertion. No direct source-line edits were
made by the human.