engine.transition is now the only writer of job status. It implements the target
table in state-transitions.md §3: claim, non-terminal metadata, explicit
terminals, idempotent re-receipt, refusal of conflicting or late signals with an
audit entry, stale-attempt rejection, and deadline timeout.
Two write paths become one. update_job_status merged fields unconditionally;
pick_pending hand-rolled a correct pending->running swap plus its own audit
mirror. Neither was wrong alone, but a rule added to one silently missed the
other, which is the shape that produced the phase 1 transport bugs. Both keep
their signatures and their preserved legacy bodies behind MAM_ENGINE_CAS=0.
A merged `status` value is routed to the request that owns it, so a raw field
write can no longer slip past the table. Getting that wrong first was caught by
the characterization tests: a metadata merge was overwriting the caller's status
with the pre-merge value.
Lock discipline is now enforced, not described. The lock covers a decision and
one record write; audit mirroring is queued and flushed after release, carrying a
monotonic transition_seq so ordering survives the move. A test watches for
subprocess, socket and sleep calls while the lock is held and asserts none.
Structural correction to my own plan, caught by a phase 1 guard: the plan put the
engine in lib_py/loop, but delegation would then have had to import a sibling,
which is exactly what mixes trees under a frozen loop. The engine belongs with
the registry writers, so it lives in lib_py/delegation and loop consumes it.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UrDNJkHmm18uu7n7JwV5Qd
The four delegation scripts become a real package. Their old paths stay as
shims because those paths are a wire contract: agent instructions, the bash
wrapper, SKILL.md, BOOTSTRAP.md, deploy/install.sh and three test modules all
call them literally.
The shim binds the lib_py.delegation *package* to the tree beside it, once per
process, and never touches sys.path. Two cheaper designs were rejected with
evidence (the context matrix now lives in the test suite):
* inserting the sibling skills dir at sys.path[0] makes the first sandbox
copy imported under pytest shadow lib_py.agents/layout/state for the whole
session, and the identity assertion cannot see it -- `is` proves same
object, not same tree.
* loading only the named module by file path leaves a module that imports
siblings pulling them from whichever tree is on the path, so a frozen
publish_event ran against live dependencies and lost half of B-13.
Binding the package fixes both: one tree for all delegation modules, the parent
lib_py untouched, and a sys.path append only when no lib_py exists anywhere
(true standalone). Bind-once rather than nearest-wins, because rebinding would
split existing references and break monkeypatching.
Also moves the env-file load off import (_load_dotenv -> ensure_env_loaded,
called by each process entry point including reconcile.sh's embedded
subscriber), so importing the library no longer mutates os.environ.
Verified: PV-1 identity+provenance, PV-4's ten import scenarios plus K1/K3/K6
in fresh interpreters, PV-5 shim byte-identity, an AST check that the package
imports no sibling lib_py module, and --help output diffed against the
pre-move capture.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UrDNJkHmm18uu7n7JwV5Qd