feat: memory compaction — progressive summarization for stored memories

[AliceLJY]

Summary

• src/memory-compactor.ts (new): Pure, dependency-free compaction module implementing the progressive summarization pattern. Clusters semantically similar memories using greedy cosine-similarity expansion (seeded by highest-importance entry), then merges each cluster into a single refined entry — deduplicating lines, taking max importance, plurality-voting on category.
• store.ts: Adds fetchForCompaction(maxTimestamp, scopeFilter, limit) — fetches old entries with raw vectors (intentionally omitted from list() for performance; compaction needs them for similarity computation).
• index.ts: Wires in memory_compact MCP tool (gated by enableManagementTools) with dry_run / min_age_days / similarity_threshold / scopes parameters. Also registers an optional gateway_start auto-compaction hook with configurable cooldown.
• openclaw.plugin.json: memoryCompaction config schema + uiHints.
• test/memory-compactor.test.mjs: 23 tests covering cosineSimilarity, buildClusters, buildMergedEntry, and runCompaction (including dry-run, empty store, orthogonal entries, scan limit).

Motivation

Without compaction, the LanceDB index accumulates fragments of the same idea across many sessions. Related memories like "prefers dark mode", "always uses dark theme", "dark mode on all apps" remain as three separate entries — each returned at retrieval time, wasting context budget and diluting precision. Progressive summarization collapses these into one high-quality entry, so the index gets more refined over time rather than noisier.

Config example

"memoryCompaction": {
  "enabled": true,
  "minAgeDays": 7,
  "similarityThreshold": 0.88,
  "cooldownHours": 24
}

Manual use (requires enableManagementTools: true)

// Preview without writing
memory_compact { dry_run: true }

// Run for specific scopes
memory_compact { scopes: ["project:myapp"], similarity_threshold: 0.92 }

Test plan

• node --test test/memory-compactor.test.mjs — 23/23 pass
• Manual: enable memoryCompaction.enabled: true in a live OpenClaw instance; confirm gateway_start log shows compaction stats
• Manual: call memory_compact with dry_run: true, verify cluster count makes sense for your LanceDB
• Verify existing auto-capture / auto-recall behavior is unchanged when memoryCompaction is absent from config

🤖 Generated with Claude Code

[NW15D]

Mar 26 18:03:18 OpenClaw node[1962]: 2026-03-26T18:03:18.841+00:00 [plugins] plugin tool name conflict (memory-lancedb-pro): memory_compact
it's ok ? it conflict with core_tools openclaw.
i use github version of plugin