Framework Update | Haystack 3.1.0
Haystack 3.1.0 highlights: (1) Experimental `CompactionHook` with `SlidingWindowCompactor` (drop old turns) and `ToolResultPruningCompactor` (replace old tool results with placeholders) for managing context blowup in long conversations; (2) `AgentTool` lets you wrap a full Agent as another Agent's tool — the caller sees only the final reply, not intermediate steps; (3) Multiple pipeline deserialization and Jinja sandbox RCE vulnerabilities patched, plus several behavioral changes requiring migration (e.g. `Agent.state_schema` semantics changed, `custom_filters` now requires `unsafe=True`).