Struct DefaultBlockCompaction 

pub struct DefaultBlockCompaction;

Default block-based compaction strategy.

Stateless — all parameters come from CompactionConfig.

• keep_first: returns turn range 0..keep_first_turns
• keep_compacted: one-liner summaries of the middle section, bounded by max_summary_tokens
• keep_recent: truncates tool outputs in the recent section to tool_output_max_lines

Trait Implementations

impl BlockCompactionStrategy for DefaultBlockCompaction

fn keep_compacted( &self, record: &LoopRecord, turn_map: &TurnMap, config: &CompactionConfig, is_most_recent: bool, ) -> Option<CompactedSection>

Basic implementation: generates per-turn one-liner summaries until max_summary_tokens is exhausted. Remaining turns are dropped.

More sophisticated strategies (e.g. LLM-based) should produce a holistic summary of ALL turns within the budget rather than dropping turns.

Summaries use Message::User role to maintain valid LLM message alternation (user→assistant→user→…). A summary replaces a full turn sequence (user + assistant + tool results) with a single user-role “[Summary]” message.

fn keep_first( &self, _record: &LoopRecord, turn_map: &TurnMap, config: &CompactionConfig, ) -> Option<TurnRange>

Determine the keep_first section: turns kept verbatim from the start. Only called for the most recent loop.

fn keep_recent( &self, record: &LoopRecord, turn_map: &TurnMap, config: &CompactionConfig, ) -> Option<CompactedSection>

Create the keep_recent section: recent turns with truncated tool outputs. Only called for the most recent loop.

fn compact( &self, record: &LoopRecord, config: &CompactionConfig, is_most_recent: bool, ) -> CompactionBlock

Assemble a CompactionBlock from the three sections. Default implementation calls the three methods above.