Turn runtime spec amended after review: context references with a
context resolver, recovery that re-issues interrupted model calls and
continues after interrupted sync tools, turn_failed.code with
model-call-limit, default maxModelCalls 20.
New session layer spec: append-only session JSONL, turn-file-first
write ordering, in-memory write-through index with startup scan,
reject-while-busy sendMessage, dedicated ask-human endpoint, deferred
v2 shapes for queueing/steering/grants/compaction.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
