Variable: looseKeyedToolCallParser

const looseKeyedToolCallParser: ToolCallParserFn;

Defined in: src/batteries/llm/chat_common/tool_parsers.ts:815

Parse the DEGENERATE keyed form a small instruct model emits when it ignores every structured tool-call grammar: the bare tool NAME on its own line, then one or more argname: value lines.

Remarks

Observed verbatim from Gemma-4 E2B on LiteRT-web (raw-captured): asked to call an answer tool it emits, with no call:/braces/brackets/JSON at all —

say_i_dont_know
reason: The documentation does not contain a definition for that.

No marker-anchored or pythonic/JSON parser claims this, so the "call" leaks into the visible answer as prose AND the turn looks like a refusal (the tool the model meant to invoke never fires). A 2B can't be reliably instructed into a format (changing the prompt's documented format did not change the output), so the robust path is to parse the shape it actually produces.

WEAK SIGNAL, gated HARD (like barePythonicToolCallParser): it only claims when the FIRST non-empty line is EXACTLY a real offered tool name (ctx.toolNames) and is followed by at least one key: value line. That gate is what keeps it from misreading ordinary prose ("Note: …", a heading with a colon). Single call only (the degenerate form has no list syntax); runs LAST in 'auto'.