Durable record: bound to the owning session id and validated at the fold (orphan-SID shape, temp path inside the host temp root) — a fork's copied parent record no longer provisions the child, and a tampered record fails loud. Private temp dir: random unguessable name persisted in the record, created exclusively (pre-existing entries and reparse points fail EEXIST). Persistence: a fresh provision kicks an immediate flush (no write-behind debounce), narrowing the crash window to the flush latency — documented as the one self-healing gap. Runner-failure rules: exit-gated on 127 so a confined command that prints the signature on a non-127 exit is never misclassified. Spawn: AssignProcessToJobObject failure terminates the suspended child (no hanging orphans). SandboxExecutionPolicy.sessionId is the branded SessionId. Boundary docs: qualifying clause on the absolutist sentences, NULL-DACL Known Limitation, 'full' scoped to the supported NTFS surface, CLM gate comment.
tool-pwsh now renders sandbox denial facts (denial marker + same-turn escalation hint, runner-failed notice on background reads) and advertises the sandbox_permissions/justification escalation pair resolved through ctx.approval before execution — the shared fail-closed sequence from dsh-sandbox, with the tool name 'pwsh'. The description teaches the ConstrainedLanguage contract under the Windows sandbox (both confined modes run pwsh in CLM: Add-Type, non-core .NET statics, COM, and reflection fail; the mode cannot be lifted — probe-verified, pinned by LANGMODE assertions in the runner suite and description assertions in the tool suite). The stale pwsh-sandbox JSDoc ('the tool owns approval') and the parity notes' superseded 'minus sandbox' claims are corrected.
Invocation is an ordinary session.prompt again: the pre-step gesture
boundary makes it deterministic host-side for every front end, so the
dedicated RPC (handler, wire schema, error codes, client face, fixtures)
and ui-skill's claim machinery are net deletions. The menu keeps decision
21 exactly — a pick lands literal /name text — plus the user-only marker
from skill.list's modelInvocable flag.
The self-hosted Linux runners ship no pwsh, and the pwshAvailable probes used spawnSync('where.exe'), which reports a missing binary as status null instead of throwing — the suites never skipped and failed with spawn pwsh ENOENT. Probe with resolvePwshPath() status instead, the same gate the coverage exemption uses. Exempt pwsh-sandbox src from coverage on pwsh-less hosts (its remaining helpers branch and the invariant companion ride the executor suites' real pwsh runs); pwsh-ful hosts keep the full 100% bar. Cover the windows-acl probe case and the runner-entry resolution in sandbox-local on Linux (chain-seam tests plus a windowsAclRunnerEntry seam) — the package's POSIX-only suites are Linux's only chance to cover the new lines. Static gate fixes: declare dsh-pwsh-sandbox in the base bundle, register the runner files entry in constraints, knip entries for the e2e suite and where.exe, regenerate the module graph. Verified in WSL (no-pwsh Linux): pwsh-sandbox 5 pass/13 skip with the exemption active, sandbox-local coverage 100%.
Review findings on #1977, each verified before acting: the 2026-08-03
declared-provider-catalog note is updated in place and cross-linked both
ways now that reasoningEfforts/compat reopened half of its rejected
alternative; resolveModelCompat inherits the catalog entry's compat only
while the resolved api still is the entry's own, so a route-level api
repoint no longer merges another protocol's shape as a completions base;
the off-with-value promise gains a request-boundary test proving pi-ai
reads thinkingLevelMap.off when the reasoning option is absent (and the
catalog-level test name stops overclaiming); the cannot-stop-thinking
wording narrows to what is actually enforced (no Off offered, explicit
Off refused — an effortless request goes out bare); the z.const(null)
comment attributes null passthrough to schemastery's nullable
short-circuit; the baseten drift-gate claim names its verification
source; and the layered-merge delete gap for dict keys is documented
under Known Limitations with the atomic-leaf follow-up in #2003.
Huanqi Cao
_Kerman
imccyu
Tianyi Cui
Turtle
Yichen Jiang