Constant TOOL_RESULT_CAP 

pub const TOOL_RESULT_CAP: usize = _; // 8_192usize

Longest tool result, in chars, prospero keeps on a ToolFinished event. Matches caliban’s STREAM_RESULT_TEXT_CAP (8 KiB), so a current caliban’s result_text passes through unchanged; the cap is prospero’s own guarantee that one tool call cannot put an unbounded body into the event stores or SSE.