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+- Added `LLMContextSummaryConfig` (summary generation params: `target_context_tokens`, `min_messages_after_summary`, `summarization_prompt`) and `LLMAutoContextSummarizationConfig` (auto-trigger thresholds: `max_context_tokens`, `max_unsummarized_messages`, plus a nested `summary_config`). These replace the monolithic `LLMContextSummarizationConfig`.
diff --git a/changelog/3863.added.md b/changelog/3863.added.md
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+- Added `LLMSummarizeContextFrame` to trigger on-demand context summarization from anywhere in the pipeline (e.g. a function call tool). Accepts an optional `config: LLMContextSummaryConfig` to override summary generation settings per request.
diff --git a/changelog/3863.changed.md b/changelog/3863.changed.md
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+- ⚠️ Renamed `LLMAssistantAggregatorParams` fields: `enable_context_summarization` → `enable_auto_context_summarization` and `context_summarization_config` → `auto_context_summarization_config` (now accepts `LLMAutoContextSummarizationConfig`). The old names still work with a `DeprecationWarning` for one release cycle.
diff --git a/changelog/3863.deprecated.md b/changelog/3863.deprecated.md
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+- Deprecated `LLMContextSummarizationConfig`. Use `LLMAutoContextSummarizationConfig` with a nested `LLMContextSummaryConfig` instead. The old class emits a `DeprecationWarning`.