Lossless Context Management plugin for OpenClaw, based on the LCM paper from Voltropy. Replaces OpenClaw's built-in sliding-window compaction with a DAG-based summarization system that preserves every message while keeping active context within model token limits.

• What it does
• Quick start
• Configuration
• Documentation
• Development
• License

Two ways to learn: read the below, or check out this super cool animated visualization.

When a conversation grows beyond the model's context window, OpenClaw (just like all of the other agents) normally truncates older messages. LCM instead:

1. Persists every message in a SQLite database, organized by conversation
2. Summarizes chunks of older messages into summaries using your configured LLM
3. Condenses summaries into higher-level nodes as they accumulate, forming a DAG (directed acyclic graph)
4. Assembles context each turn by combining summaries + recent raw messages
5. Provides tools (lcm_grep, lcm_describe, lcm_expand) so agents can search and recall details from compacted history

Nothing is lost. Raw messages stay in the database. Summaries link back to their source messages. Agents can drill into any summary to recover the original detail.

It feels like talking to an agent that never forgets. Because it doesn't. In normal operation, you'll never need to think about compaction again.

• OpenClaw with plugin context engine support
• Node.js 22+
• An LLM provider configured in OpenClaw (used for summarization)

Use OpenClaw's plugin installer (recommended):

openclaw plugins install @martian-engineering/lossless-claw

If you're running from a local OpenClaw checkout, use:

pnpm openclaw plugins install @martian-engineering/lossless-claw

For local plugin development, link your working copy instead of copying files:

openclaw plugins install --link /path/to/lossless-claw
# or from a local OpenClaw checkout:
# pnpm openclaw plugins install --link /path/to/lossless-claw

The install command records the plugin, enables it, and applies compatible slot selection (including contextEngine when applicable).

Note: If your OpenClaw config uses plugins.allow, make sure both lossless-claw and any active plugins you rely on remain allowlisted. In some setups, narrowing the allowlist can prevent plugin-backed integrations from loading, even if lossless-claw itself is installed correctly. Restart the gateway after plugin config changes.

In most cases, no manual JSON edits are needed after openclaw plugins install.

If you need to set it manually, ensure the context engine slot points at lossless-claw:

{
  "plugins": {
    "slots": {
      "contextEngine": "lossless-claw"
    }
  }
}

Restart OpenClaw after configuration changes.

LCM is configured through a combination of plugin config and environment variables. Environment variables take precedence for backward compatibility.

Add a lossless-claw entry under plugins.entries in your OpenClaw config:

{
  "plugins": {
    "entries": {
      "lossless-claw": {
        "enabled": true,
        "config": {
          "freshTailCount": 64,
          "leafChunkTokens": 80000,
          "newSessionRetainDepth": 2,
          "contextThreshold": 0.75,
          "incrementalMaxDepth": 1,
          "ignoreSessionPatterns": [
            "agent:*:cron:**"
          ],
          "summaryModel": "anthropic/claude-haiku-4-5",
          "expansionModel": "anthropic/claude-haiku-4-5",
          "delegationTimeoutMs": 300000
        }
      }
    }
  }
}

leafChunkTokens controls how many source tokens can accumulate in a leaf compaction chunk before summarization is triggered. The default is 20000, but quota-limited summary providers may benefit from a larger value to reduce compaction frequency. summaryModel and summaryProvider let you pin compaction summarization to a cheaper or faster model than your main OpenClaw session model. expansionModel does the same for lcm_expand_query sub-agent calls (drilling into summaries to recover detail). delegationTimeoutMs controls how long lcm_expand_query waits for that delegated sub-agent to finish before returning a timeout error; it defaults to 120000 (120s). When unset, the model settings still fall back to OpenClaw's configured default model/provider. See Expansion model override requirements for the required subagent trust policy when using expansionModel.

If you want lcm_expand_query to run on a dedicated model via expansionModel or LCM_EXPANSION_MODEL, OpenClaw must explicitly trust the plugin to request sub-agent model overrides.

Add a subagent policy under plugins.entries.lossless-claw and allowlist the canonical provider/model target you want the plugin to use:

{
  "models": {
    "openai/gpt-4.1-mini": {}
  },
  "plugins": {
    "entries": {
      "lossless-claw": {
        "enabled": true,
        "subagent": {
          "allowModelOverride": true,
          "allowedModels": ["openai/gpt-4.1-mini"]
        },
        "config": {
          "expansionModel": "openai/gpt-4.1-mini"
        }
      }
    }
  }
}

• subagent.allowModelOverride is required for OpenClaw to honor plugin-requested per-run provider/model overrides.
• subagent.allowedModels is optional but recommended. Use "*" only if you intentionally want to trust any target model.
• The chosen expansion target must also be available in OpenClaw's normal model catalog. If it is not already configured elsewhere, add it under the top-level models map as shown above.
• If you prefer splitting provider and model, set config.expansionProvider and use a bare config.expansionModel.

Plugin config equivalents:

• ignoreSessionPatterns
• statelessSessionPatterns
• skipStatelessSessions
• newSessionRetainDepth
• summaryModel
• summaryProvider
• delegationTimeoutMs

Environment variables still win over plugin config when both are set.

For compaction summarization, lossless-claw resolves the model in this order:

1. LCM_SUMMARY_MODEL / LCM_SUMMARY_PROVIDER
2. Plugin config summaryModel / summaryProvider
3. OpenClaw's default compaction model/provider
4. Legacy per-call model/provider hints

If summaryModel already includes a provider prefix such as anthropic/claude-sonnet-4-20250514, summaryProvider is ignored for that choice. Otherwise, the provider falls back to the matching override, then OPENCLAW_PROVIDER, then the provider inferred by the caller.

LCM_FRESH_TAIL_COUNT=64
LCM_LEAF_CHUNK_TOKENS=20000
LCM_INCREMENTAL_MAX_DEPTH=1
LCM_CONTEXT_THRESHOLD=0.75

• freshTailCount=64 protects the last 64 messages from compaction, giving the model more recent context for continuity.
• leafChunkTokens=20000 limits how large each leaf compaction chunk can grow before LCM summarizes it. Increase this when your summary provider is quota-limited and frequent leaf compactions are exhausting that quota.
• incrementalMaxDepth=1 runs one condensed pass after each leaf compaction by default. Set to 0 for leaf-only behavior, a larger positive integer for a deeper cap, or -1 for unlimited cascading.
• contextThreshold=0.75 triggers compaction when context reaches 75% of the model's window, leaving headroom for the model's response.

Lossless-claw distinguishes OpenClaw's two session-reset commands:

• /new keeps the active conversation row and all stored summaries, but prunes context_items so the next turn rebuilds context from retained summaries instead of the fresh tail.
• /reset archives the active conversation row and creates a new active row for the same stable sessionKey, giving the next turn a clean LCM conversation while preserving prior history.

newSessionRetainDepth (or LCM_NEW_SESSION_RETAIN_DEPTH) controls how much summary structure survives /new:

• -1: keep all existing context items
• 0: keep all summaries, drop only fresh-tail messages
• 1: keep d1+ summaries
• 2: keep d2+ summaries; recommended default
• 3+: keep only deeper, more abstract summaries

Lossless-claw currently applies these storage semantics through the before_reset hook only. User-facing confirmation text after /new or /reset must be emitted by OpenClaw's command handlers.

Use ignoreSessionPatterns or LCM_IGNORE_SESSION_PATTERNS to keep low-value sessions completely out of LCM. Matching sessions do not create conversations, do not store messages, and do not participate in compaction or delegated expansion grants.

Pattern rules:

• * matches any characters except :
• ** matches anything, including :
• Patterns match the full session key

Examples:

• agent:*:cron:** excludes cron sessions for any agent, including isolated run sessions like agent:main:cron:daily-digest:run:run-123
• agent:main:subagent:** excludes all main-agent subagent sessions
• agent:ops:** excludes every session under the ops agent id

Environment variable example:

LCM_IGNORE_SESSION_PATTERNS=agent:*:cron:**,agent:main:subagent:**

Plugin config example:

{
  "plugins": {
    "entries": {
      "lossless-claw": {
        "config": {
          "ignoreSessionPatterns": [
            "agent:*:cron:**",
            "agent:main:subagent:**"
          ]
        }
      }
    }
  }
}

Use statelessSessionPatterns or LCM_STATELESS_SESSION_PATTERNS for sessions that should still be able to read from existing LCM context, but should never create or mutate LCM state themselves. This is useful for delegated or temporary sub-agent sessions that should benefit from retained context without polluting the database.

When skipStatelessSessions or LCM_SKIP_STATELESS_SESSIONS is enabled, matching sessions:

• skip bootstrap imports
• skip message persistence during ingest and after-turn hooks
• skip compaction writes and delegated expansion grant writes
• can still assemble context from already-persisted conversations when a matching conversation exists

Pattern rules are the same as ignoreSessionPatterns, and matching is done against the full session key.

Environment variable example:

LCM_STATELESS_SESSION_PATTERNS=agent:*:subagent:**,agent:ops:subagent:**
LCM_SKIP_STATELESS_SESSIONS=true

Plugin config example:

{
  "plugins": {
    "entries": {
      "lossless-claw": {
        "config": {
          "statelessSessionPatterns": [
            "agent:*:subagent:**",
            "agent:ops:subagent:**"
          ],
          "skipStatelessSessions": true
        }
      }
    }
  }
}

LCM preserves history through compaction, but it does not change OpenClaw's core session reset policy. If sessions are resetting sooner than you want, increase OpenClaw's session.reset.idleMinutes or use a channel/type-specific override.

{
  "session": {
    "reset": {
      "mode": "idle",
      "idleMinutes": 10080
    }
  }
}

• session.reset.mode: "idle" keeps a session alive until the idle window expires.
• session.reset.idleMinutes is the actual reset interval in minutes.
• OpenClaw does not currently enforce a maximum idleMinutes; in source it is validated only as a positive integer.
• If you also use daily reset mode, idleMinutes acts as a secondary guard and the session resets when either the daily boundary or the idle window is reached first.
• Legacy session.idleMinutes still works, but OpenClaw prefers session.reset.idleMinutes.

Useful values:

• 1440 = 1 day
• 10080 = 7 days
• 43200 = 30 days
• 525600 = 365 days

For most long-lived LCM setups, a good starting point is:

{
  "session": {
    "reset": {
      "mode": "idle",
      "idleMinutes": 10080
    }
  }
}

• Configuration guide
• Architecture
• Agent tools
• TUI Reference
• lcm-tui
• Optional: enable FTS5 for fast full-text search

# Run tests
npx vitest

# Type check
npx tsc --noEmit

# Run a specific test file
npx vitest test/engine.test.ts

index.ts                    # Plugin entry point and registration
src/
  engine.ts                 # LcmContextEngine — implements ContextEngine interface
  assembler.ts              # Context assembly (summaries + messages → model context)
  compaction.ts             # CompactionEngine — leaf passes, condensation, sweeps
  summarize.ts              # Depth-aware prompt generation and LLM summarization
  retrieval.ts              # RetrievalEngine — grep, describe, expand operations
  expansion.ts              # DAG expansion logic for lcm_expand_query
  expansion-auth.ts         # Delegation grants for sub-agent expansion
  expansion-policy.ts       # Depth/token policy for expansion
  large-files.ts            # File interception, storage, and exploration summaries
  integrity.ts              # DAG integrity checks and repair utilities
  transcript-repair.ts      # Tool-use/result pairing sanitization
  types.ts                  # Core type definitions (dependency injection contracts)
  openclaw-bridge.ts        # Bridge utilities
  db/
    config.ts               # LcmConfig resolution from env vars
    connection.ts           # SQLite connection management
    migration.ts            # Schema migrations
  store/
    conversation-store.ts   # Message persistence and retrieval
    summary-store.ts        # Summary DAG persistence and context item management
    fts5-sanitize.ts        # FTS5 query sanitization
  tools/
    lcm-grep-tool.ts        # lcm_grep tool implementation
    lcm-describe-tool.ts    # lcm_describe tool implementation
    lcm-expand-tool.ts      # lcm_expand tool (sub-agent only)
    lcm-expand-query-tool.ts # lcm_expand_query tool (main agent wrapper)
    lcm-conversation-scope.ts # Conversation scoping utilities
    common.ts               # Shared tool utilities
test/                       # Vitest test suite
specs/                      # Design specifications
openclaw.plugin.json        # Plugin manifest with config schema and UI hints
tui/                        # Interactive terminal UI (Go)
  main.go                   # Entry point and bubbletea app
  data.go                   # Data loading and SQLite queries
  dissolve.go               # Summary dissolution
  repair.go                 # Corrupted summary repair
  rewrite.go                # Summary re-summarization
  transplant.go             # Cross-conversation DAG copy
  prompts/                  # Depth-aware prompt templates
.goreleaser.yml             # GoReleaser config for TUI binary releases

MIT