Readonly_ReadonlyagentThe subagent to dispatch — resolved against compiled agent names.
Optional ReadonlyneedsOptional input contract the step reads from its predecessor's result().ok.
When present, the whole-harness registry (generate-harness) emits a
per-edge Handoff<> assertion so a CROSS-FILE handoff mismatch (a missing
field or wrong type vs the prior step's ok) is a tsc error naming the
field. Absent needs = no handoff check (today's behavior, the string-path
backstop). Built by needs(...), the same builder a typed pipeStep uses.
Optional ReadonlytaskOptional task hint passed to the worker.
One step on a railway: dispatch a flat subagent (the "activity").