Two coupled fixes from the 2026-05-08 smoke-test trace:
1. pm_cannot_execute_code is now scoped to i_will_work_on (the
EXECUTION verb) only. Pre-fix it also fired on i_will_plan, which
deadlocked any code-typed parent: cell_pm couldn't plan, so couldn't
transition parent to in_progress, so couldn't delegate. PMs PLAN
code-typed parents and DELEGATE the work — that's exactly the verb
we were blocking.
2. delegate.task_type is now REQUIRED at both the HTTP boundary
(DelegateRequest) and the choreographer dataclass (DelegateInputs).
The pre-fix default of 'code' silently changed semantics whenever a
caller forgot the field — main-pm's call in the smoke trace omitted
it, schema defaulted to 'code', and the cell PM downstream was
wedged. Also drops the choreographer's task.task_type fallback
(the DB column is NOT NULL anyway).
Plus middleware coverage tests for the parallel ServiceError →
4xx handler hierarchy added in the prior session, restoring 100%
coverage across the touched files.
Tests: 3101 passing, 100% coverage, ruff clean.
Service signatures are (task_id, agent_id, ...) but choreographer was
calling (agent_id, task_id). Production claim path silently returned
None; unit tests pinned the buggy order so the bug was invisible. Swap
all 7 call sites and update test assertions. Add a regression pin
that locks in the correct order.
Ports five pre-gateway predicates that were dropped when the gateway
displaced the MCP claim handler. Predicates restored from
roboco/mcp/tasks/handlers/_helpers.py:124-204 and
roboco/mcp/tasks/handlers/claim.py:121-180 at commit 254cc93:
- SEQUENCE_ORDER_VIOLATION: a sibling task with sequence < N must be
in completed/cancelled before sibling N can be claimed.
- ALREADY_ACTIVE: agent cannot claim while owning an in_progress /
claimed / verifying task other than the one being resumed.
- PAUSED_TASKS_EXIST: agent cannot claim while paused tasks exist.
- PM_CANNOT_EXECUTE_CODE: cell_pm/main_pm cannot claim task_type=code.
- ROLE_TYPED_CLAIM: developer claim is restricted to
code/research/design; qa/documenter must use claim_review /
claim_doc_task.
All five guards run inside Choreographer._run_claim_guards before
i_will_work_on / i_will_plan / claim_review / claim_doc_task mutate
state. Skip flags isolate guards that don't apply to a verb (e.g.,
PM-code skipped on QA verb, role-typed skipped on PM verb).
The guards live in roboco/services/gateway/claim_guards.py so
choreographer.py stays focused on orchestration.
Existing tests updated to provide the new mock primings; the
permissive auto-mock behavior they relied on no longer applies.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Renn F