v0.6.0 — Compactor trait, StrategyCompactor

v0.6.0 — Compactor trait, StrategyCompactor

Compaction gets a single, clean entry point. The old "config + trigger + strategy" trio is replaced by one Compactor trait, with a StrategyCompactor that bundles a trigger closure, a strategy, and an optional summarisation backend. Breaking — hence the 0.6 bump.

What's Changed

Compactor trait + StrategyCompactor

CompactionConfig, CompactionTrigger, ItemCountTrigger, AgentBuilderCompactionExt, and the internal LegacyCompactor wrapper are gone. Register a compactor on the agent builder via the new AgentBuilderCompactorExt::compactor:

use agentkit_compaction::{
    AgentBuilderCompactorExt, CompactionPipeline, DropFailedToolResultsStrategy,
    DropReasoningStrategy, NestedLoopCompactionBackend, StrategyCompactor,
    SummarizeOlderStrategy,
};
use agentkit_loop::Agent;

let compactor = StrategyCompactor::builder()
    .item_count_trigger(64)
    .strategy(
        CompactionPipeline::new()
            .with_strategy(DropReasoningStrategy::new())
            .with_strategy(DropFailedToolResultsStrategy::new())
            .with_strategy(SummarizeOlderStrategy::new(8)),
    )
    .backend(NestedLoopCompactionBackend { adapter: adapter.clone() })
    .build()?;

let agent = Agent::builder()
    .model(adapter)
    .compactor(compactor)
    .build()?;

For stateful triggers (e.g. token-window aware), supply a closure that reads external state:

use agentkit_compaction::{CompactionReason, StrategyCompactor, SummarizeOlderStrategy};

let compactor = StrategyCompactor::builder()
    .trigger(move |transcript, _point| {
        (transcript.len() > 64).then_some(CompactionReason::TranscriptTooLong)
    })
    .strategy(SummarizeOlderStrategy::new(8))
    .build()?;

CompactionRequest slimmed down

session_id and turn_id are removed from CompactionRequest — strategies that need session context read it from the surrounding LoopCtx instead. CompactionRequest::for_turn and CompactionRequest::with_turn_id are gone; use CompactionRequest::new(transcript, reason) and .with_metadata(...).

Examples + docs migrated

All four examples/openrouter-* agents (chat, parallel, compaction, context-window-compaction) now use StrategyCompactor. Book chapters ch02/ch03/ch04/ch06/ch16/ch19/ch21/ch22/ch23 rewritten against the new surface.

Clippy pass

12 trivial lints fixed across the workspace: collapsible match/if, unused imports, while let → while, map_or → is_none_or, needless borrows. (One real refactor in cerebras-chat left for a follow-up.)

Migration notes

• Replace CompactionConfig::new(trigger, strategy).with_backend(...) + .compaction(config) with:

  let compactor = StrategyCompactor::builder()
      .trigger(...)         // Fn(&[Item], MutationPoint) -> Option<CompactionReason>
      .strategy(...)        // single CompactionStrategy (use CompactionPipeline to chain)
      .backend(...)         // optional, for SummarizeOlderStrategy
      .build()?;
  agent_builder.compactor(compactor)

• ItemCountTrigger::new(n) → StrategyCompactor::builder().item_count_trigger(n).
• Custom impl CompactionTrigger types: convert to a closure passed to .trigger(...), or implement the new Compactor trait directly if you need state.
• CompactionRequest::for_turn(session_id, turn_id, transcript, reason) → CompactionRequest::new(transcript, reason); read session/turn info from the surrounding loop context.
• AgentBuilderCompactionExt import paths change to AgentBuilderCompactorExt.

Commits

• refactor(compaction): replace CompactionConfig/Trigger with StrategyCompactor (3226515)

Full Changelog: v0.5.1...v0.6.0