Bug type

Behavior bug (incorrect output/state without crash)

Beta release blocker

No

Summary

OpenClaw was configured with plugins.slots.contextEngine = "lossless-claw" and plugins.entries.lossless-claw.enabled = true, but the gateway repeatedly logged that lossless-claw was not registered and fell back to legacy.

Steps to reproduce

1. Run OpenClaw with lossless-claw installed under ~/.openclaw/extensions/lossless-claw/.
2. Configure ~/.openclaw/openclaw.json with plugins.slots.contextEngine = "lossless-claw".
3. Confirm plugins.entries.lossless-claw.enabled = true.
4. Start or restart the LaunchAgent-managed OpenClaw gateway.
5. Use the agent normally.
6. Observe repeated gateway log entries:

[context-engine] Context engine "lossless-claw" is not registered; falling back to default engine "legacy".

7. Change only plugins.slots.contextEngine from "lossless-claw" to "legacy" and restart the gateway.
8. Observe that no new lossless-claw is not registered messages appear after the restart timestamp.

Expected behavior

If plugins.slots.contextEngine = "lossless-claw" and plugins.entries.lossless-claw.enabled = true, OpenClaw should either register and use the lossless-claw context engine or surface a clear plugin registration/load error explaining why it cannot be registered.

Actual behavior

The gateway repeatedly logged:

[context-engine] Context engine "lossless-claw" is not registered; falling back to default engine "legacy".

The plugin appeared installed and enabled, but the selected context engine was not registered at runtime. After changing only plugins.slots.contextEngine to "legacy" and restarting the gateway, no new lossless-claw is not registered messages appeared.

OpenClaw version

2026.5.2 observed locally

Operating system

macOS 26.4.1

Install method

npm global

Model

xai/grok-4.3 primary; anthropic/claude-haiku-4-5 configured as lossless-claw summaryModel

Provider / routing chain

OpenClaw gateway using configured local providers; primary runtime model observed as xai/grok-4.3

Additional provider/model setup details

plugins.entries.lossless-claw.config.summaryModel was set to anthropic/claude-haiku-4-5.

Relevant observed plugin state:

• plugins.slots.contextEngine = "lossless-claw" before workaround
• plugins.entries.lossless-claw.enabled = true
• Plugin installed at ~/.openclaw/extensions/lossless-claw/
• Manifest declared:
  • id: lossless-claw
  • kind: context-engine
• ~/.openclaw/plugins/installs.json showed resolvedVersion 0.9.2
• ~/.openclaw/extensions/lossless-claw/package.json showed version 0.9.3
• openclaw plugins list --json reported a persisted-registry-stale-source warning
• lcm.db existed and contained data, but lossless-claw was not active as the registered context engine

Logs, screenshots, and evidence

Relevant repeated gateway log entry:


[context-engine] Context engine "lossless-claw" is not registered; falling back to default engine "legacy".


Bounded diagnostic findings:


OpenClaw version: 2026.5.2
Install: global npm at /opt/homebrew/lib/node_modules/openclaw
Gateway: LaunchAgent-managed
Config before workaround: plugins.slots.contextEngine = "lossless-claw"
Config after workaround: plugins.slots.contextEngine = "legacy"
Plugin path: ~/.openclaw/extensions/lossless-claw/
Plugin enabled: true
Manifest id: lossless-claw
Manifest kind: context-engine
installs.json resolvedVersion: 0.9.2
package.json version on disk: 0.9.3
openclaw plugins list --json warning: persisted-registry-stale-source


Minimal workaround diff:


-      "contextEngine": "lossless-claw"
+      "contextEngine": "legacy"


After the workaround:


Gateway restarted cleanly.
PID changed after restart.
No new "lossless-claw is not registered" messages appeared after the restart timestamp.
Normal chat behavior was stable under legacy.
lcm.db and lcm-files remained preserved and untouched.

Impact and severity

Affected users/systems/channels:

Single observed local OpenClaw installation using lossless-claw as the configured context engine.

Severity:

Medium to High. The configured context engine was unavailable at runtime, causing repeated context-engine fallback noise and requiring a manual switch to legacy.

Frequency:

Repeatedly observed before switching to legacy; no new occurrences observed after switching to legacy and restarting.

Consequence:

lossless-claw data remained preserved on disk, but the lossless-claw context engine was inactive. Legacy mode did not read lcm.db, so Lossless Claw memory was unavailable while using the workaround.

Additional information

This was observed and diagnosed on OpenClaw 2026.5.2, but I do not know whether 2026.5.2 is the first affected version. Similar symptoms may have existed earlier, so I am not filing this as a confirmed regression.

Backups were created before changing configuration:

~/.openclaw/openclaw.json.bak-20260503-205746
~/.openclaw/lcm.db.bak-20260503-205753
~/.openclaw/lcm-files.bak-20260503-205757
~/.openclaw/state-backup-20260503-205800.tgz

The lcm.db backup passed:

PRAGMA integrity_check = ok

Observed lcm.db contents before switching to legacy:

conversations: 26
messages: 26,850
summaries: 275
context_items: 1,625
large_files: 5

After switching to legacy, lcm.db stopped receiving new writes and remained preserved on disk.

Last known good version:

NOT_ENOUGH_INFO

First known bad version:

NOT_ENOUGH_INFO