tractor/ai/prompt-io/opencode/20260919_context_fault_status.md

Prompt and human design

The human prototyped ContextCancelReason, ContextStatus, and a rename of the context-owned nursery. They requested implementation after saving the IB fixes, on a separate downstream branch, with Trio’s minimum version in a separate commit. Their design separates runtime-layer transport faults from reported remote task failures/cancellations.

Design references supplied by the human: https://github.com/goodboy/tractor/issues/400 https://github.com/goodboy/tractor/issues/22 https://github.com/goodboy/tractor/issues/368 https://github.com/goodboy/tractor/issues/388

Response summary

Context._status is the single store for outcome, cancellation protocol, and handshake/lifecycle state. On explicit human instruction, the agent removed the generated typed descriptors and duplicate Context declarations. Internal accesses now use Context._status directly; there is no moved-field constructor compatibility layer. Policy and live resources remain on Context. Status diagnostics render only declared state. Public properties, wait_for_result(), and the deprecated result() method remain available.

ContextCancelReason is shallow-frozen and includes context/actor/peer identity, an opaque scope token and explicit fault origin. The retained exception is mutable and may retain traceback resources. Local validation and boxed remote errors remain distinguishable even with equal peer IDs. Raw transport loss no longer causes self-cancel classification to read remote-error-only attributes before checking its exception type.

Files changed

• tractor/_context.py: status extraction, metadata and direct access.
• tractor/_exceptions.py: preserve local validation provenance.
• tractor/runtime/_rpc.py: nursery rename and direct status access.
• tractor/_streaming.py: stream state and result status access.
• tractor/msg/_ops.py: final message drain status access.
• tractor/runtime/_runtime.py: Context cancellation status access.
• tractor/devx/debug/_trace.py: copied nursery rename documentation.
• tractor/devx/debug/_tty_lock.py: copied nursery rename documentation.
• tests/test_context_status.py: twenty reason/state/public API cases.
• tests/test_context_stream_semantics.py: status assertions and the overrun test double’s ContextStatus allocation.
• tests/test_ipc_eof.py: status assertions.
• tests/msg/test_pldrx_limiting.py: status assertions.
• tests/test_inter_peer_cancellation.py: status assertions.

Verification

The initial implementation passed 86 tests: 16 context-status, 65 context-stream semantics and 5 EOF cases. Used the existing original worktree interpreter with Trio0.34.0 and per-process source overrides; no installed packages or live services were changed. Automatic reaping was disabled. Broader cancellation suites needing reaper-provided fixtures remain unverified.

After the human-directed simplification, the targeted run passed 91 tests: 20 context-status, 65 context-stream semantics, 5 EOF, and the overlapping service-nursery cancellation regression. The first run found a SimpleNamespace overrun test double still declaring _stream_opened directly; it now allocates ContextStatus. The complete targeted run passed after that correction and removal of mk_context’s redundant result initialization.

A separate run passed all 8 payload-limiting cases. All 7 cases in test_inter_peer_cancellation.py stopped at fixture setup because track_orphaned_uds_per_test belongs to the disabled reaper plugin. No cleanup plugin was enabled to bypass this constraint.

Both runs used the existing ib_disconnect_cleanup/py313/bin/python, Trio 0.34.0, and PYTHONPATH ordered as this worktree, that interpreter’s site-packages, then piker/py313 site-packages. TRACTOR_SPAWN_METHOD and TRACTOR_LOGLEVEL were unset. Pytest arguments, after python -m pytest:

-p no:tractor._testing._reap
tests/test_context_status.py
tests/test_context_stream_semantics.py
tests/test_ipc_eof.py
tests/test_resource_cache.py::test_moc_service_nursery_cancellation_completes_exit
-q

Separate process:

-p no:tractor._testing._reap
tests/msg/test_pldrx_limiting.py
tests/test_inter_peer_cancellation.py
-q

The source audit accounts for all 70 old production direct accesses: 49 rewritten in _context.py, its redundant mk_context assignment removed, and 20 rewritten across seven functions in four other files. All 33 old direct test accesses across five files were addressed: 29 migrated and four compatibility assertions replaced with status initialization/isolation and public API assertions. The additional test-double keyword dependency was found by execution and corrected. Remaining same-named attributes belong to Actor, ActorNursery or Channel. Added Python lines fit 69 columns; git diff –check passes.

A private pre-adjustment index tree and the real index SHA256 are recorded in ignored .claude runtime state for review. The existing plan-build helper captured the private tree without git add. The real index and HEAD remain unchanged; all remediation is unstaged.

Human contribution accounting

The prototype classes, reason= experiment, nursery rename, downstream sequencing, fault-layer distinction, and separate dependency boundary were human-directed. The human accepted immutable identity metadata and excluding policies/resources from the status store. The agent added the actual authoritative store, descriptor delegation, provenance classification, diagnostics and regressions in the initial output.

The human subsequently rejected descriptor delegation and its self-imposed constructor/attribute compatibility tests. They directed the single-store simplification, the precise 11-field migration scope, preservation of public APIs and the deprecated result method, fault origin policy, comments/TODO markers and _scope_tn rename. They also required preserving their staged prototype and leaving the remediation unstaged. These are human-directed agent edits, not direct manual source edits. The original raw generated record is retained unchanged. Acceptance remains human-owned.

Limits

This does not add new supervision/reconnect APIs, inject Cancelled subclasses, or selectively uncancel scopes. First cancellation reason does not necessarily track the latest remote error. copy.copy(Context) shares the status object, as it also shares other live context resources. Private-field constructor compatibility and dataclasses.replace() compatibility assertions were removed on human instruction.