muse-spark (opencode-go, Responses wire) occasionally serializes its next native
tool call onto the text channel as <atem:function_calls>…</atem:function_calls>
instead of a function_call item. With real tool work earlier in the turn and
finish_reason=stop, the literal XML is then delivered as the turn's final answer
(observed on a production cron worker: the turn ended on the full XML block; the
task itself had executed).
Teach the tool-call XML patterns an optional namespace prefix (?:[\w.-]+:)? on
the open/close tags and the unterminated-opener tail, in every copy of the
stripper: agent/agent_runtime_helpers.py (_TOOL_CALL_BLOCK_PATTERNS,
_STRAY_TOOL_CALL_CLOSER_PATTERN, _UNTERMINATED_TOOL_CALL_PATTERN) and the
display-side cli.py::_strip_reasoning_tags, which the test suite requires to stay
in sync. Covered positions: closed block, stray closer, unterminated opener
(stream cut mid-serialization).
With the block stripped to nothing, the existing empty-response recovery path
(agent/turn_final_response.py) re-prompts the model instead of shipping XML as
the answer.
Refs #103483 (the native-call XML leaking as text is listed there as not covered yet).
Tests: tests/agent/test_strip_reasoning_tags_cli.py — full block and
cut-mid-serialization tail, each asserted against both strippers. Proven red on
base: 2 failed / 4 passed without the pattern change; 6 passed with it.
60735cbf81