Run Level 2 validation probes

[burtenshaw]

This PR runs local Level 2 probes, grades startup/reward/observation/state, and records replayable evidence with explicit skips for unfinished checks. Builds on #1179; third of three stacked PRs tracked in #1177.

[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

Autofix Details

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Schema worker truncates Unicode payloads
  • The grader now serializes worker payloads without ASCII escaping, with a regression test covering Unicode traces within the wire budget.

Or push these changes by commenting:

@cursor push c8f6b6ffb8

Preview (c8f6b6ffb8)

diff --git a/src/openenv/validation/graders/runtime/basic.py b/src/openenv/validation/graders/runtime/basic.py
--- a/src/openenv/validation/graders/runtime/basic.py
+++ b/src/openenv/validation/graders/runtime/basic.py
@@ -143,7 +143,10 @@
         try:
             checked = subprocess.run(
                 [sys.executable, "-I", str(worker)],
-                input=json.dumps({"schema": schema, "observations": observations}),
+                input=json.dumps(
+                    {"schema": schema, "observations": observations},
+                    ensure_ascii=False,
+                ),
                 capture_output=True,
                 text=True,
                 timeout=5,

diff --git a/tests/test_validation/test_runtime_grading.py b/tests/test_validation/test_runtime_grading.py
--- a/tests/test_validation/test_runtime_grading.py
+++ b/tests/test_validation/test_runtime_grading.py
@@ -219,6 +219,45 @@
     )
 
 
+def test_unicode_trace_within_wire_budget_reaches_schema_worker_intact(tmp_path):
+    text = "\U0001f600" * 150_000
+    rows = []
+    for index in range(6):
+        operation = "reset" if index == 0 else "step"
+        rows.append(
+            WireExchange(
+                operation,
+                json.dumps({"type": operation}),
+                json.dumps(
+                    {
+                        "type": "observation",
+                        "data": {
+                            "observation": {"counter": index, "text": text},
+                            "reward": None if index == 0 else 0,
+                            "done": False,
+                        },
+                    },
+                    ensure_ascii=False,
+                ),
+            )
+        )
+    assert (
+        sum(
+            len(row.request_json.encode()) + len(row.response_json.encode())
+            for row in rows
+        )
+        < 8 * 1024 * 1024
+    )
+    assert len(json.dumps([text] * len(rows))) > 10 * 1024 * 1024
+    schema = copy.deepcopy(OBSERVATION_SCHEMA)
+    schema["properties"]["text"] = {"type": "string"}
+    schema["required"].append("text")
+
+    result = ObservationSchemaGrader().run(subject_with(tmp_path, rows, schema=schema))
+
+    assert result.status is CheckStatus.PASS
+
+
 @pytest.mark.parametrize(
     "field,value", [("done", None), ("done", "false"), ("done", 0), ("observation", [])]
 )

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Alignment Review Report

Two-tier review of the RFC-008 Level 2 execution slice 3 (startup, reward, observation, state checks). This is a stacked PR (base ben/rfc008-l2-02-docker), so the repo's test/lint workflows don't gate it — the results below are from running the suites locally, plus the dedicated runtime-validation CI job.

Automated Checks

• Lint: PASS (PR files). ruff format --check, usort check, and ruff check are all clean on the 14 changed .py files. The full-tree lint.sh failure (57 ruff format + usort exit 2) is pre-existing envs/ + test_grid_world.py/test_julia_env.py drift, not introduced here.
• Debug code: CLEAN. No print/breakpoint/pdb/TODO/FIXME in the PR's src/ files.
• Tests (run locally): green. 97 new runtime unit tests pass; full tests/test_validation = 292 passed (incl. test_policy, test_schema_sync, test_runner); tests/test_cli/test_validate.py = 11 passed (no regression — contrast slice 1). The Docker integration test (test_runtime_cli.py, @pytest.mark.docker) isn't runnable in this env, but the dedicated "Runtime validation / Linux Docker" CI job passed.

Open RFCs Context

• RFC 008 — Environment Auto-Validation (Status: In Review, @zkwentz). This PR implements the "Level 2 execution amendment", slice 3, and is faithful to it: bounded public probe loader (65 536 B / depth 32 / 10 000 nodes / 1–100 actions, duplicate-key + non-finite rejection, no seed/episode_id override); a single-session collector recording raw uncoerced request/response strings; reset-reward-may-be-null / step-reward-must-be-a-finite-number-in-range-excluding-booleans; the state identity + step_count contract; policy v2 adding runtime.startup (v1 rejected for runtime); the FAIL/ERROR/SKIP taxonomy; unsupported network/GPU refused before build; an explicit SKIP inventory for not-yet-implemented Level-2 checks; and a redacted evidence bundle.
• No other RFC (001/002/003/004) is in conflict; RFC 004 rubrics remain leveraged-not-required.

Tier 1: Fixes Required

• None. No mechanical, type, import, or security defects found.

Tier 2: Alignment Discussion

Principle Conflicts

None identified. The change actively reinforces several invariants — worth affirming:

• Dual API boundary / agent isolation: the collector drives the Gym-like reset/step/state loop as validation orchestration (agent_boundary: api), never as an agent tool — no agent-facing exposure of simulation control.
• Client–server separation: validation talks to the subject purely over the wire (httpx/websockets); it imports nothing from server/.
• Rewards in environment: graders only observe the environment's own reward against the declared range; no external reward computation.
• No credential exposure: strong throughout — httpx(trust_env=False), LaunchSpec inherits no host env, artifact redaction (secret keys + token regex), failure reasons carry only exception types, and tests assert secrets never reach reports/traces.
• Security depth (nice work): JSON-Schema evaluation is sandboxed in a disposable python -I subprocess with CPU/AS rlimits + a wall-clock deadline (ReDoS → finding, not hang); non-local $ref/$dynamicRef are rejected and the worker uses an empty referencing.Registry (no SSRF/file retrieval); source_digest opens files O_NOFOLLOW and rejects symlinks.

Three small, non-blocking notes are left inline (report coherence on mid-run source change; --policy exit-code semantics; HTTP /schema vs the WebSocket-only direction).

RFC Conflicts

ALIGNMENT FLAG: Implementation landing while RFC 008 is still In Review

• Principle/RFC at stake: RFC 008 (Status: In Review) — Level 2 execution amendment
• The concern: the standing sequencing flag for this stack — the slice freezes real behavior (manifest schema v2, severity policy v2, the validation.execution sidecar contract) against an amendment that is not yet Accepted. The implementation matches the current amendment text; the ask is to confirm those L2 contracts are settled before further slices stack on them. Non-blocking.
• Suggested reviewer: @zkwentz (RFC author); @Darktex (principles/invariants owner, git blame b1a92e1 on INVARIANTS.md)

Summary

• 0 mechanical issues to fix (Tier 1)
• 1 alignment point for human review (RFC-008 In-Review sequencing) + 3 minor non-blocking inline notes
• 0 hard RFC conflicts — the implementation is faithful to the RFC 008 Level 2 amendment

  

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[bot-ci-comment]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

[cursor]

Stale comment

Exact-head CI is red on the same inherited failure as #1178: test_write_report_validation_report_only. Fix lands in #1178; please rebase after that greens. Holding deeper Level-2 probe review until then.

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[cursor]

Stale Bugbot comment from a previous run.

[cursor]

Stale comment

REQUEST_CHANGES at c7e89896

Still blocked on inherited #1178 CI (test_write_report_validation_report_only). Separately, Bugbot’s High finding on this head is real:

collector treats exceptions from the final close send / WebSocket context exit as collection failures (failure_reason), and runtime graders then FAIL the episode even when reset/step/state already succeeded. Teardown noise must not fail a measured episode.

Also track (Medium):

1. Schema worker stdin.read(10MB) can truncate large observation batches under the 8MB trace cap
2. socket.send is not bound by episode_timeout_s (only pre-checked via remaining())

Fix close-failure handling here; rebase after #1178 greens. Not Thursday 0.6.0 cargo.

  

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

Autofix Details

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Malformed envelopes crash runtime graders
  • Runtime graders now convert AttributeError from non-object envelope data into a FAIL finding while preserving the collector failure reason.

Or push these changes by commenting:

@cursor push ea46021702

Preview (ea46021702)

diff --git a/src/openenv/validation/graders/runtime/basic.py b/src/openenv/validation/graders/runtime/basic.py
--- a/src/openenv/validation/graders/runtime/basic.py
+++ b/src/openenv/validation/graders/runtime/basic.py
@@ -58,7 +58,14 @@
             problems.append(evidence.failure_reason)
         try:
             problems.extend(self.check(subject, evidence))
-        except (ValueError, TypeError, KeyError, RecursionError, OverflowError):
+        except (
+            ValueError,
+            TypeError,
+            KeyError,
+            AttributeError,
+            RecursionError,
+            OverflowError,
+        ):
             problems.append("malformed runtime evidence")
         return CheckResult(
             check_id=self.check_id,

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[cursor]

Stale comment

REQUEST_CHANGES at 2950de74

Inherited #1178 CI is green now. The High teardown issue remains on this head: close/WS-exit exceptions still set failure_reason and fail graders after a successful reset/step/state episode.

Also still open (Medium): schema-worker 10MB stdin truncate; socket.send not bound by episode_timeout_s.

Not Thursday 0.6.0 cargo.

  

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[cursor]

Stale comment

REQUEST_CHANGES at d724b7e5 (High/Medium fixed; Low residual)

Fixed (prior High/Medium):

• Completed-episode teardown: complete + best-effort close/send no longer sets failure_reason / fails graders; regressions in test_runtime_transport.py cover close-send, close-failure, and genuine in-episode failure precedence.
• Transport sends are bounded via _bounded_call + raw-socket abort against episode_timeout_s.
• Schema worker input budget raised / wire JSON preserved (response_json / schema_json) so unicode and compact 1e9 episodes within wire limits no longer truncate.

Still open (Low): graders call data.get(...) after data = response["data"] without isinstance(data, dict). The collector can store a raw exchange then raise on a non-object data envelope; ObservationSchemaGrader / state graders then AttributeError outside the (ValueError, TypeError, …) catch → grader ERROR instead of contract FAIL. Guard with isinstance(data, dict) (or equivalent) before .get.

Holding approval for that guard (+ exact-head CI still in flight). Not Thursday 0.6.0 cargo.

  

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 2 potential issues.

There are 3 total unresolved issues (including 1 from previous review).

Autofix Details

Bugbot Autofix prepared fixes for both issues found in the latest run.

• ✅ Fixed: Episode timeout silently capped at 300s
  • Runtime collection now honors the manifest's validated episode timeout without imposing an unrelated 300-second cap.
• ✅ Fixed: Schema worker stdin encoding can fail
  • The schema worker subprocess now explicitly encodes text input as UTF-8 regardless of the parent locale.

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[cursor]

Stale comment

REQUEST_CHANGES at d724b7e5 (Bugbot refresh)

Prior High/Medium (teardown / bounded send / schema wire budget) remain fixed.

New Medium: runner.py silently caps collection at min(..., 300.0) while policy bounds allow max_episode_timeout_s=3600. Legal longer episodes can false-FAIL. Use the policy-validated declared timeout (or align the cap with the bound).

Still open Lows:

1. Malformed non-object data → AttributeError in graders (ERROR vs FAIL).
2. Schema-worker stdin: parent text=True/ensure_ascii=False vs worker UTF-8 stdin.buffer (locale-dependent).

Bugbot autofix is active — will re-review on the next head. Not Thursday 0.6.0 cargo.

  

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[cursor]

Stale comment

REQUEST_CHANGES at f405e4ec (autofix progress)

Fixed this head:

• Medium timeout cap: collection now uses manifest.resources.episode_timeout_s directly; regression asserts 600.0 is passed through.
• Low schema-worker encoding: parent subprocess.run(..., encoding="utf-8") aligns with UTF-8 stdin.buffer reads.

Still open (Low): graders still call data.get(...) without isinstance(data, dict) after loading a possibly non-object envelope the collector stored before rejecting. That AttributeError escapes the grader catch set → ERROR instead of contract FAIL.

Holding approval for that guard. Exact-head CI still running. Not Thursday 0.6.0 cargo.

  

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

Autofix Details

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Startup failures hide provider diagnostics
  • Runtime startup outcomes now retain the sanitized exception details for runtime-plan, startup, and provider failures, with regression coverage for each path.

Or push these changes by commenting:

@cursor push 0577dc4585

Preview (0577dc4585)

diff --git a/src/openenv/validation/runner.py b/src/openenv/validation/runner.py
--- a/src/openenv/validation/runner.py
+++ b/src/openenv/validation/runner.py
@@ -185,27 +185,27 @@
             "runtime.startup", CheckStatus.SKIP, str(exc), started=started
         )
         checks = []
-    except RuntimePlanError:
+    except RuntimePlanError as exc:
         result = _outcome(
             "runtime.startup",
             CheckStatus.FAIL,
-            "runtime plan is missing, unsafe or invalid",
+            str(exc),
             started=started,
         )
         checks = []
-    except StartupError:
+    except StartupError as exc:
         result = _outcome(
             "runtime.startup",
             CheckStatus.FAIL,
-            "subject failed build or readiness; inspect the Docker fixture/build inputs",
+            str(exc),
             started=started,
         )
         checks = []
-    except ProviderError:
+    except ProviderError as exc:
         result = _outcome(
             "runtime.startup",
             CheckStatus.ERROR,
-            "provider could not complete a bounded operation",
+            str(exc),
             started=started,
         )
         checks = []

diff --git a/tests/test_validation/test_runtime_execution.py b/tests/test_validation/test_runtime_execution.py
--- a/tests/test_validation/test_runtime_execution.py
+++ b/tests/test_validation/test_runtime_execution.py
@@ -7,7 +7,7 @@
 
 import pytest
 from openenv.validation.policy import load_policy, PolicyError
-from openenv.validation.providers import StartupError
+from openenv.validation.providers import ProviderError, StartupError
 from openenv.validation.report import CheckResult
 from openenv.validation.runner import run_validation, source_digest
 from openenv.validation.runtime.artifacts import write_runtime_bundle
@@ -172,6 +172,8 @@
     provider = FakeRuntimeProvider()
     report = run_validation(package, max_level=Level.RUNTIME, provider=provider)
     assert report.verdict.value == "fail"
+    result = next(r for r in report.results if r.check_id == "runtime.startup")
+    assert "invalid runtime plan" in result.evidence[0]
     assert not provider.builds
 
 
@@ -185,9 +187,23 @@
     report = run_validation(package, max_level=Level.RUNTIME, provider=provider)
     result = next(r for r in report.results if r.check_id == "runtime.startup")
     assert result.status is CheckStatus.FAIL
+    assert result.evidence == ["subject build failed"]
     assert report.verdict.value == "fail"
 
 
+def test_provider_failure_diagnostics_are_visible(package):
+    provider = FakeRuntimeProvider()
+
+    def failed_build(*args):
+        raise ProviderError("provider deadline elapsed")
+
+    provider.build = failed_build
+    report = run_validation(package, max_level=Level.RUNTIME, provider=provider)
+    result = next(r for r in report.results if r.check_id == "runtime.startup")
+    assert result.status is CheckStatus.ERROR
+    assert result.evidence == ["provider deadline elapsed"]
+
+
 @pytest.mark.parametrize("failure", [RuntimeError, KeyboardInterrupt])
 def test_collector_crash_or_cancel_always_tears_down(package, monkeypatch, failure):
     provider = FakeRuntimeProvider()

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Stale comment

REQUEST_CHANGES at 16d68689 (CI green; Bugbot refresh)

Prior High/Medium (teardown, bounded send, schema wire budget, timeout cap, UTF-8 encoding) remain fixed. Exact-head CI is green.

New Medium: runtime.startup swallows sanitized StartupError / RuntimePlanError / ProviderError details into generic strings — authors lose actionable diagnostics. Surface a bounded sanitized reason.

Still open (Low): malformed non-object data → grader AttributeError (ERROR vs FAIL).

Bugbot autofix is active. Not Thursday 0.6.0 cargo.

  

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

Autofix Details

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Teardown failure hides startup findings
  • Teardown failures now only mark cleanup incomplete, preserving the existing runtime startup and collection findings.

Or push these changes by commenting:

@cursor push 61b156dfda

Preview (61b156dfda)

diff --git a/src/openenv/validation/runner.py b/src/openenv/validation/runner.py
--- a/src/openenv/validation/runner.py
+++ b/src/openenv/validation/runner.py
@@ -234,12 +234,6 @@
                 cleanup["completed"] = True
             except Exception:
                 cleanup["completed"] = False
-                result = _outcome(
-                    "runtime.startup",
-                    CheckStatus.ERROR,
-                    "subject teardown failed",
-                    started=started,
-                )
     return [result, *checks], attempted, plan, evidence, inspection, cleanup

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[cursor]

Stale comment

REQUEST_CHANGES at eb7a40b1 (Bugbot Medium)

Prior APPROVE at this tip is withdrawn. Autofix is still in flight; do not merge until the teardown overwrite is fixed.

Tier 1

• src/openenv/validation/runner.py _runtime() finally: when running.stop() fails, the existing runtime.startup result is replaced with a generic teardown ERROR. That discards prior PASS/FAIL/ERROR evidence (provider reason, collection failure_reason, etc.) and contradicts the helper docstring (“retain failure evidence through teardown”).

Required: keep the original result (and its evidence); record cleanup failure via cleanup["completed"] = False and/or append a separate note without overwriting attribution. Add a regression that fails primary startup/collection then fails stop(), asserting the primary finding remains visible.

Not Thursday 0.6.0 cargo until merge.

  

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[cursor]

Stale comment

Base retargeted to main after #1179 merge (26c9465e). Tip 29c58015 still has the two Bugbot mediums (uncaught post-run source_digest, teardown KeyboardInterrupt) — REQUEST_CHANGES holds. Watching Autofix / next push.

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[burtenshaw]

Rebased onto current main (26c9465e) after #1179 merged and resolved the conflict while preserving both sets of regression tests.

The three latest findings are fixed in ccca191e: source-digest failures and teardown interrupts preserve reports/artifacts, and the reward grader handles non-object envelopes explicitly. All 13 checks, including Linux Docker validation and Bugbot, pass on this commit; 378 local validation tests pass. All review threads are resolved. Ready for re-review; the earlier changes-requested review still needs to be refreshed.

[cursor]

Stale Bugbot comment from a previous run.

[cursor]

Initial digest errors skip the report

Medium Severity

The initial source_digest call is not on the report-preserving path. A symlink or non-regular file now raises before any checks run, so authors get an internal-error exit instead of a report. The same ValueError and OSError cases after collection are caught and recorded.

Additional Locations (2)

• src/openenv/validation/runner.py#L52-L64
• src/openenv/validation/runner.py#L347-L350

 

^{Reviewed by Cursor Bugbot for commit bea5115. Configure here.}

[cursor]

Stale comment

REQUEST_CHANGES at exact tip bea5115d — Bugbot Medium (valid):

Initial source_digest skips the report path. digest_before = source_digest(target) (~L282) is uncaught. Symlink / non-regular-file ValueErrors (and OSError from os.open) abort with an internal error before any checks run. Post-collection source_digest already catches (ValueError, OSError) and records a reportable failure — initial digest should do the same (or otherwise emit a ValidationReport ERROR) for symmetry with the Autofix that landed in ccca191e.

Autofix is already kicked off — will re-review when the tip advances. Keep out of Thursday 0.6.0 cargo until green.

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

Autofix Details

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Failed digest still reads rejected source
  • Validation now reports the digest failure without parsing, re-digesting, or running the rejected package source.

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[cursor]

Stale comment

REQUEST_CHANGES still holds at 65be5dd8 — prior Autofix fixed the uncaught initial digest, but Bugbot Medium is valid on the new shape:

Failed digest still reads rejected source. Catching source_digest and setting digest_before = "" then continues into parser.parse and _runtime before stamping static.manifest ERROR. Those paths can follow the same symlinks / non-regular files the digest rejected, so host content may enter the report or build context before the ERROR is recorded.

Fail closed: on initial digest (ValueError, OSError), emit a ValidationReport with a reportable ERROR (and empty/"" source_digest) and return without parse/runtime. Keep the regression that asserts no internal-error exit and no private path leakage.

Autofix already kicked off — will re-review when the tip advances. Keep out of Thursday 0.6.0.

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[cursor]

Stale comment

@zkwentz — Ben wants your review before folding this into Thursday’s 0.6.0 cut. Tip refreshed onto current main (16240f19) so you’re not reviewing a stale branch; CI will re-run on this head.

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

Autofix Details

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Interrupt during close drops episode
  • WebSocket close teardown now swallows KeyboardInterrupt like other best-effort teardown failures, preserving completed or previously failed episode evidence.

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[cursor]

Stale comment

REQUEST_CHANGES at exact tip 16240f19 — Bugbot Medium (valid) after merge-main re-scan:

Interrupt during post-episode websocket close drops a finished episode. _bounded_call re-raises KeyboardInterrupt; the teardown except Exception handlers miss it. A completed collection then surfaces as interrupt: startup → ERROR, graders never run, failure_phase still names the last successful op.

Post-episode close/teardown should treat KeyboardInterrupt as best-effort (same as other teardown failures) once complete is True, or convert to RuntimeCollectionInterrupted without discarding measured evidence. Autofix is already kicked off — will re-review on the new tip.

Hold fold into Thursday 0.6.0 until this is green + Zach’s review.

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[cursor]

Re-APPROVE at dd59275f (Bugbot Autofix)

Confirmed the Medium was real: post-episode KeyboardInterrupt during _bounded_call close/teardown bypassed except Exception, so a finished collection was surfaced as RuntimeCollectionInterrupted and graders never ran.

Autofix is correct and minimal — teardown except (Exception, KeyboardInterrupt) on both the graceful close send and the socket close — with a focused regression in test_runtime_transport.py. Local transport suite: 10 passed.

Still waiting on @zkwentz for the human gate before folding into Thursday 0.6.0. Exact-head CI is re-running on this tip.

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[cursor]

Re-APPROVE at d94f0218

Autofix force-pushed the same close-interrupt fix (collector teardown catches KeyboardInterrupt; transport suite 10/10). Prior APPROVE was on superseded tip dd59275f (+1 test-line churn only).

Still waiting on @zkwentz + exact-head CI before Thursday 0.6.0 fold.

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Source digest uses Unix-only flags
  • Made O_NONBLOCK optional in source_digest and added a regression test for platforms where the flag is unavailable.

_{You can send follow-ups to the cloud agent here.}

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