Salvages the intent of #33136 (@Brixyy) onto current main. The original PR
was written against the pre-refactor monolithic run_agent.py and added a
top-level _is_nonretryable_local_validation_error() helper. Both target
functions have since been extracted to agent/conversation_loop.py:2869,
so the salvage applies the equivalent guard inline at that canonical
location rather than reintroducing the helper.
## Why
After #33042 made our own Codex consumer structurally immune to NoneType
crashes, third-party shims, mocked clients, and any future code path that
hasn't migrated could still surface TypeError: 'NoneType' object is not
iterable as a wire-shape mismatch. The agent loop's classifier currently
treats ALL TypeError as a local programming bug and aborts non-retryable
— users on stale Telegram/gateway turns saw bare "Non-retryable error
(HTTP None)" with no recovery.
This is a provider/SDK shape mismatch, not a local programming bug. The
retry/fallback path should run, not be short-circuited.
## What
agent/conversation_loop.py: extend is_local_validation_error to exclude
TypeErrors whose message matches the NoneType-not-iterable shape (case-
insensitive, both "NoneType" and "not iterable" must appear).
tests/run_agent/test_jsondecodeerror_retryable.py:
- update the mirror predicate to match the production check
- add TestNoneTypeNotIterableIsRetryable class with 3 tests (the basic
shape, message variants, unrelated TypeErrors still abort)
- add TestAgentLoopSourceHasNoneTypeCarveOut to enforce the source-level
invariant matches the test mirror
## Validation
tests/run_agent/test_jsondecodeerror_retryable.py +
tests/run_agent/test_31273_402_not_retried.py → 14/14 passing
Co-authored-by: Brixyy <subrtt@gmail.com>
dc9d677d59