Dispatcher-spawned Kanban workers are finite one-shot processes, so detached delegation completions can outlive their only consumer. Mark that runtime as unable to deliver async completions and reuse the synchronous delegation fallback, returning required child results before the worker exits.\n\nAlso make unsupported-session notes runtime-generic and cover the delayed-child lifecycle regression.\n\nRefs #63169
run_agent._dispatch_delegate_task forces background=True for every top-level
delegation, and async_delivery_supported() returns True for any session that
never binds the capability. On runners that cannot receive a completion after
their turn ends, that combination silently discards every subagent result: the
model gets a dispatch handle, ends its turn, and reports 'waiting for results'.
Two such runners never bind the capability:
* hermes -z (one-shot) prints one final response and exits. It bypasses cli.py,
so nothing drains process_registry.completion_queue (only the interactive
process_loop and the gateway watchers do).
* cron run_job clears the HERMES_SESSION_* routing keys, so a completion event
carries session_key="" — _enrich_async_delegation_routing cannot resolve it
and _inject_watch_notification drops it ("no routing metadata"). By then
run_job has already shipped the job's final response via _deliver_result;
there is no turn left to re-enter. Worse, get_current_session_key() can fall
back to the ambient os.environ HERMES_SESSION_KEY, so a cron subagent's output
can be routed into an unrelated user chat rather than merely dropped.
Add declare_stateless_channel() and bind it in both runners, routing
delegate_task to its existing inline/synchronous path — the same fallback the
stateless HTTP adapter already relies on, and the fix suggested in #63142. The
helper binds only the capability: set_session_vars() would also latch
_session_context_engaged, which a pure single-process one-shot must not trigger.
Also correct two agent-facing strings that hardcoded 'stateless HTTP API' as the
only channel without async delivery (delegate_tool, terminal_tool); they now name
the actual condition.
Repro (before): hermes -z 'Use delegate_task to spawn a subagent that replies
BANANA. Report its reply.' -> "Waiting for the subagent's response...", exit 0,
no BANANA. After: BANANA is returned in-turn.
Fixes#53027Fixes#63142
* fix(api-server): stop silently promising async delivery on stateless HTTP path
terminal(notify_on_complete=True / watch_patterns) and delegate_task(background=True)
silently no-op'd on the API server / WebUI path (#10760): the watcher / detached
child registered, but every API-server route (OpenAI-spec /v1/chat/completions
and /v1/responses, plus the proprietary /v1/runs SSE stream) tears down its
channel when the turn ends, and APIServerAdapter.send() is a no-op stub. A
completion that fires after the response closed had nowhere to go — from the
agent side, indistinguishable from a hang.
There is no spec-compliant surface to wake the agent later on a stateless HTTP
client, so make the no-op honest instead of silent:
- Add a per-adapter capability flag supports_async_delivery (default True;
APIServerAdapter = False), propagated into a HERMES_SESSION_ASYNC_DELIVERY
contextvar via async_delivery_supported(). Toggle on the adapter, not a
hardcoded platform string — a future stateless adapter is correct-by-default.
- terminal: when delivery is unsupported, skip watcher registration, force
notify_on_complete off, and return a notify_unsupported note telling the
agent to process(action='poll').
- delegate_task: when delivery is unsupported, fall back to SYNCHRONOUS
execution (work runs and returns in the same response) with a note, instead
of handing out a handle that never resolves.
CLI (in-process completion_queue) and the real gateway platforms are unchanged.
Fixes#10760
* refactor(api-server): route session binding through a single no-delivery chokepoint
Add APIServerAdapter._bind_api_server_session() and route both agent-entry
paths (_run_agent for /v1/chat/completions + /v1/responses, and the /v1/runs
_run_sync path) through it. The helper hardwires platform="api_server" and
async_delivery=False with no async_delivery parameter to pass, so a future
route added to the API server physically cannot reintroduce the silent
no-op (#10760) by forgetting to mark the channel as non-delivering.
The binding stays request-scoped (cleared per turn), so a session resumed
later on a delivering interface (CLI / gateway platform) re-binds fresh and
is NOT blocked — the no-delivery decision tracks the interface handling the
current turn, never the session.
