[JoeyPatricio]

Purpose

FunctionGemmaToolParser.extract_tool_calls returns only the text before the first <start_function_call> as content. Anything the model writes after the last <end_function_call>, or between two calls, is dropped. The streaming path emits that same text as content deltas, so the same model output gives a different answer depending on stream:

model output: <start_function_call>call:get_weather{city:<escape>Tokyo<escape>}<end_function_call>Let me check that for you.

non-streaming: content=None                          tool_calls=[get_weather]
streaming    : content='Let me check that for you.'  tool_calls=[get_weather]

With two calls and prose around them, non-streaming returns 'Sure.' and streaming returns 'Sure. Now the time. Done.'.

The cause is vllm/tool_parsers/functiongemma_tool_parser.py:126-129, which slices model_output[:content_end] where content_end is the first start token. This change walks the regex matches with finditer and collects the text outside the call blocks as content. Tool call extraction is unchanged.

Same bug class as #56263 (deepseek_v3) and #55199 (parser engine), in the FunctionGemma parser.

Test Plan

pytest tests/tool_parsers/test_functiongemma_tool_parser.py -q
pre-commit run --files vllm/tool_parsers/functiongemma_tool_parser.py tests/tool_parsers/test_functiongemma_tool_parser.py

Two unit tests cover trailing text and text around two calls. A parity test runs the same output through both modes with tests.tool_parsers.utils.run_tool_extraction and the gpt2 tokenizer, then checks that content, names and arguments match.

Test Result

Without the fix: 4 failed, 15 passed. With it: 19 passed. All pre-commit hooks on the two files pass (ruff check, ruff format, mypy 3.10, typos, SPDX). CPU only, tokenizer only, no model run.

AI assistance

The bug was found by a script that diffs each tool parser's streaming and non-streaming output. Claude Code helped write the fix and tests. I reviewed every changed line and ran the tests and pre-commit hooks locally.

[claude]

Claude Code Review

This pull request is from a fork — automated review is disabled. A repository maintainer can comment @claude review to run a one-time review.

[github-actions]

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