lossless-claw

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.

Table of contents

• What it does
• Quick start
• Configuration
• Commands And Skill
• Session Migration CLI
• Documentation
• Development
  • Line endings
• Security
• License

What it does

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.

Commands And Skill

The package installs an agent-oriented lcm shell CLI and includes a bundled lossless-claw skill plus plugin commands for supported OpenClaw chat/native command providers.

The shell CLI reads lcm.db without modifying conversation data. Its only write command sets one validated Lossless config value in openclaw.json:

lcm status
lcm conversations show --session-key 'agent:main:example'
lcm messages tail --conversation-id 42
lcm summaries list --conversation-id 42 --depth 0 --recency 7d
lcm config get freshTailCount
lcm config set freshTailCount 96

JSON is the default output. List commands use bounded keyset pagination. See Lossless Claw CLI for commands, filters, path precedence, output fields, config-write safety, and exit codes.

The native OpenClaw command surface provides in-session operations:

• /lossless shows version, enablement/selection state, DB path and size, summary counts, and summary-health status
• /lossless backup creates a timestamped backup of the current LCM SQLite database
• /lossless doctor scans for broken or truncated summaries
• /lossless doctor maintenance reports active actionable compaction debt separately from inactive historical debt, grouped by reason, without writing
• /lossless doctor apply maintenance <conversation-id> confirm-inactive administratively closes one eligible inactive debt row after creating a SQLite backup
• /lossless doctor apply repairs broken summaries in the current conversation after the normal safety preflight
• /lossless doctor apply <conversation-id> confirm-offline repairs a specific conversation after its active channel path has been paused or moved away; targeted repair is restricted to authorized OpenClaw command senders and always requires the explicit offline confirmation
• /lossless doctor clean shows read-only high-confidence junk diagnostics for archived subagents and cron sessions under every configured OpenClaw agent id, plus NULL-key orphaned subagent runs
• /lossless status shows plugin, conversation, and maintenance state including deferred compaction debt
• /lcm is the shorter alias for /lossless

Supported native command examples:

• /lossless
• /lossless backup
• /lossless doctor
• /lossless doctor maintenance
• /lossless doctor apply maintenance 42 confirm-inactive
• /lossless doctor apply 42 confirm-offline
• /lossless doctor clean
• /lcm

The package does not register these OpenClaw root subcommands:

• openclaw lossless
• openclaw lcm
• openclaw /lossless
• openclaw /lcm

The bundled skill focuses on configuration, diagnostics, architecture, and recall-tool usage. Its reference set lives under skills/lossless-claw/references/.

Deferred compaction debt on an active conversation is actionable maintenance pressure. Debt on an archived or otherwise inactive conversation is historical: normal stable-session maintenance cannot select that conversation, so /lossless doctor maintenance reports it separately and shows a bounded set of recent examples. Closing historical debt requires the exact confirm-inactive token and a successful file-backed SQLite backup. The close records an operator-ignored resolution on the maintenance row only; it does not run compaction and does not delete or rewrite conversations, messages, summaries, or context items. If that conversation later receives a genuine new debt request, the prior administrative resolution is cleared and the row becomes pending again.

Programmatic control

Lossless-claw also exposes an optional host-facing context-engine control contract for OpenClaw gateways that support context-engine capabilities and control dispatch. The contract is intentionally smaller than the native slash command surface:

• status returns whether an LCM conversation is active and the current stored message count.
• doctor returns a bounded, sanitized warning list for summary-health issues.

Programmatic control never returns transcript text, local database paths, backup paths, credentials, provider debug, or shell output.

This surface is capability-gated by the OpenClaw host. At the time of this change there is not yet a stable OpenClaw release with the required context-engine control endpoints; downstream users should treat it as unavailable unless their host advertises the matching capability, for example through the pending openclaw/openclaw#98060 contract or an equivalent downstream gateway.

Session Migration CLI

lossless-claw-migrate-sessions is a one-time shell CLI for backfilling OpenClaw JSONL session files into lcm.db after lossless-claw was disabled, missing, or installed after sessions already existed. It is not a background replay loop and it does not run summarization.

Run it in dry-run mode first:

npx --package @martian-engineering/lossless-claw@latest lossless-claw-migrate-sessions --state-dir ~/.openclaw

Apply the import only after reviewing the dry-run output:

npx --package @martian-engineering/lossless-claw@latest lossless-claw-migrate-sessions --state-dir ~/.openclaw --apply

The command defaults to ${OPENCLAW_STATE_DIR:-~/.openclaw} and ${OPENCLAW_STATE_DIR:-~/.openclaw}/lcm.db. --apply creates a timestamped SQLite backup before writing when the database already exists. Use --file <path> or repeatable --sessions-dir <path> for targeted imports, --since <iso-date> or --limit <n> to narrow a batch, and --json for machine-readable output.

Quick start

Prerequisites

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

Compatibility: lossless-claw requires OpenClaw 2026.7.2-beta.2 or newer. That beta is the first published build with the branch-safe visible transcript projection used to bootstrap SQLite-backed sessions; stable 2026.7.1 does not provide it. If you cannot use a beta or upgrade OpenClaw, stay on a lossless-claw release compatible with your installed OpenClaw version.

On OpenClaw hosts that advertise the durable context-engine turn contract, LosslessClaw declares current-turn transcript fencing and commits each accepted turn through an atomic idempotency ledger. Older supported hosts continue to use the existing afterTurn compatibility path.

Breaking upgrade: Before upgrading, remove transcriptGcEnabled and autoRotateSessionFiles from plugins.entries.lossless-claw.config. OpenClaw rejects keys that are absent from the plugin manifest, so either removed key prevents Lossless Claw from loading.

Install the plugin

Lossless Claw 1.0 stable releases use npm's latest channel. The beta channel remains available for prerelease testing.

Use OpenClaw's plugin installer (recommended):

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

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

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

Use exact versions only for rollback or reproducible canary testing. OpenClaw records an exact install spec such as @martian-engineering/lossless-claw@0.12.0 as a pinned update track, so OpenClaw plugin update sync will keep that version until you move back to the stable track:

openclaw plugins update @martian-engineering/lossless-claw@latest

For local plugin development, build your working copy first, then link it instead of copying files:

cd /path/to/lossless-claw
pnpm build

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

Re-run pnpm build after local source changes so the linked plugin's dist/ output stays current.

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, allowlist the plugin id lossless-claw plus any other active plugins you rely on. Do not add command tokens or aliases like lossless or /lcm to plugins.allow; that setting only accepts plugin ids. 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.

Configure OpenClaw

Ensure the context engine slot points at lossless-claw and explicitly allow its conversation prompt hook:

{
  "plugins": {
    "slots": {
      "contextEngine": "lossless-claw"
    },
    "entries": {
      "lossless-claw": {
        "hooks": {
          "allowConversationAccess": true
        }
      }
    }
  }
}

OpenClaw builds that protect before_prompt_build as a conversation-access hook require this grant. Without it, the context engine still loads, but OpenClaw blocks Lossless's static recall-policy prompt hook and logs the missing setting. The grant belongs beside config, not inside it.

Restart OpenClaw after configuration changes.

Configuration

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

Plugin config

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

{
  "plugins": {
    "entries": {
      "lossless-claw": {
        "enabled": true,
        "hooks": {
          "allowConversationAccess": true
        },
        "llm": {
          "allowModelOverride": true,
          "allowedModels": ["openai/gpt-5.4-mini"]
        },
        "config": {
          "freshTailCount": 64,
          "leafChunkTokens": 80000,
          "newSessionRetainDepth": 2,
          "contextThreshold": 0.75,
          "contextThresholdOverrides": [
            {
              "name": "large-context-models",
              "match": { "modelContextWindowMin": 900000 },
              "contextThreshold": 0.15
            },
            {
              "name": "telegram-sessions",
              "match": { "sessionPattern": "agent:*:telegram:**" },
              "contextThreshold": 0.3
            }
          ],
          "incrementalMaxDepth": 1,
          "cacheAwareCompaction": {
            "enabled": true,
            "cacheTTLSeconds": 300
          },
          "ignoreSessionPatterns": [
            "agent:*:cron:**",
            "agent:*:**:active-memory:**",
            "agent:*:dreaming-narrative-**"
          ],
          "proactiveThresholdCompactionMode": "deferred",
          "summaryModel": "openai/gpt-5.4-mini",
          "expansionModel": "openai/gpt-5.4-mini",
          "delegationTimeoutMs": 300000,
          "summaryTimeoutMs": 60000,
          "summaryCallWindowMs": 600000,
          "summaryMaxCallsPerWindow": 24,
          "summarySpendBackoffMs": 1800000
        }
      }
    }
  }
}

The ignoreSessionPatterns entries in this example are storage exclusions. Matching cron, active-memory, and OpenClaw memory-core dreaming narrative sessions do not create LCM conversation rows or store messages in LCM.

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 request a cheaper or faster compaction model through OpenClaw's api.runtime.llm.complete capability; OpenClaw still owns provider dispatch and auth. Explicit summary model requests require llm.allowModelOverride and matching llm.allowedModels policy entries for lossless-claw. 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). summaryTimeoutMs controls the per-call timeout for model-backed LCM summarization; it defaults to 60000 (60s). summaryMaxCallsPerWindow, summaryCallWindowMs, and summarySpendBackoffMs bound repeated non-auth summarization spend per session. 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.

Environment variables

Deferred proactive compaction is also the default. Set proactiveThresholdCompactionMode or LCM_PROACTIVE_THRESHOLD_COMPACTION_MODE to inline only if you need legacy foreground compaction behavior. In deferred mode, lossless-claw records one coalesced prompt-mutating debt item after the turn, leaves background maintain() to process only non-prompt-mutating work while Anthropic cache is still hot, and then consumes that debt pre-assembly once the cache is cold or the prompt is approaching overflow.

Expansion model override requirements

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.

For most setups, openai/gpt-5.4-mini is a better starting point than Anthropic Haiku because it is cheap, fast, and does not depend on Anthropic quota remaining.

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.
• openclaw doctor --fix can add the required subagent policy for a configured expansionModel. If a host still rejects a stale or unavailable override, lcm_expand_query retries once without the override so recall does not fail hard.

Plugin config equivalents:

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

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

Summary model priority

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. Runtime/session model/provider hints from OpenClaw

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.

Summary calls are dispatched through OpenClaw's runtime LLM layer, so auth profiles, OAuth refresh, API keys, base URLs, and provider-specific request preparation remain host-owned. Run openclaw doctor --fix after adding explicit summary model overrides if you want OpenClaw to add the matching plugins.entries.lossless-claw.llm policy.

Recommended starting configuration

LCM_FRESH_TAIL_COUNT=64
LCM_LEAF_CHUNK_TOKENS=20000
LCM_INCREMENTAL_MAX_DEPTH=1
LCM_CONTEXT_THRESHOLD=0.75
LCM_SUMMARY_MODEL=openai/gpt-5.4-mini
LCM_EXPANSION_MODEL=openai/gpt-5.4-mini

• freshTailCount=64 protects the last 64 messages from compaction, expanding through the newest user when needed so its assistant/tool suffix cannot be separated from the active instruction.
• 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.
• contextThresholdOverrides optionally picks a different threshold for matching model ids, model context-window ranges, or session patterns. If no rule matches, LCM falls back to contextThreshold.

Session exclusion patterns

Session reset semantics

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.

Lossless-claw no longer rewrites active OpenClaw transcripts for GC or session rotation. SQLite-backed OpenClaw owns active transcript storage; Lossless keeps durable conversation, summary, and recall data in its own SQLite database. If you want an LCM database snapshot before maintenance, run /lossless backup.

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 applies /new pruning through before_reset and uses session_end to catch transcript rollovers such as /reset, idle or daily session rotation, compaction session replacement, and deletions. User-facing confirmation text after /new or /reset must still 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.

Cron scheduler keys (agent:<agent>:cron:<job>...) are isolated automatically when OpenClaw reuses the same sessionKey for a new runtime sessionId: lossless-claw archives the prior active run and creates a fresh LCM conversation for the new run. Leave cron sessions out of ignoreSessionPatterns when they need in-run LCM compaction.

Pattern rules:

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

Examples:

• agent:*:cron:** excludes cron sessions for any agent when you want to bypass LCM entirely
• agent:*:**:active-memory:** excludes active-memory sessions under nested session-key prefixes; the ** segment is intentionally broad because it spans colon-separated session-key segments
• agent:*:dreaming-narrative-** excludes OpenClaw memory-core dreaming narrative sessions; OpenClaw builds those keys with the dreaming-narrative- prefix (source)
• agent:main:subagent:** excludes all main-agent subagent sessions
• agent:ops:** excludes every session under the ops agent id

Treat these examples as storage exclusions. Matching sessions do not create LCM conversation rows or store messages in LCM, so use them only for lanes whose history can stay outside LCM.

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:**"
          ]
        }
      }
    }
  }
}

Stateless session patterns

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
        }
      }
    }
  }
}

OpenClaw session reset settings

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
    }
  }
}

Documentation

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

Development

# Build (bundles TypeScript to dist/index.js)
pnpm build

# Run tests
npx vitest

# Type check
npx tsc --noEmit

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

Project structure

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
  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

Line endings

This repository codifies LF line endings through .gitattributes so diffs stay stable across macOS, Linux, and Windows development environments.

• Git should store text files with LF endings in the repository.
• The root * text=auto eol=lf rule normalizes newly added text files.
• Common source, documentation, lockfile, template, and config extensions are listed explicitly so contributors and tooling see the expected policy.
• Binary assets and SQLite/database files are marked binary to avoid unsafe newline conversion.
• If your editor or operating system prefers CRLF locally, keep the repository rules authoritative and avoid committing CRLF-only rewrites.
• After changing line-ending rules, prefer a focused normalization commit so future functional changes remain easy to review.

Security

Please report suspected vulnerabilities privately. See SECURITY.md for the supported disclosure process and response expectations.

License

MIT