omlx Provider Fails to Report Token Usage — Dashboard Shows ?/131k (?%) and Compactions: 0

[l-jessie]

Describe the bug

When using the omlx provider (MLX local inference via http://127.0.0.1:8200/v1), the OpenClaw dashboard UI fails to correctly display or track context window usage and compaction statistics. Specifically, the /status output shows 📚 Context: ?/131k (?%) and 🧹 Compactions: 0 even when the session has accumulated substantial conversation history.

The ? placeholders indicate that OpenClaw cannot resolve token counts from the omlx provider's response, making it impossible to monitor how close the session is to its 131k context window limit or verify whether auto-compaction is functioning properly.

To Reproduce

1. Configure the omlx provider in openclaw.json with a local MLX endpoint (e.g., http://127.0.0.1:8200/v1) serving Qwen3.6-35B-A3B-UD-MLX-4bit with contextWindow: 131072
2. Start a direct chat session and send multiple messages to build up conversation history
3. Run /status or check the dashboard session card
4. Observe 📚 Context: ?/131k (?%) instead of actual token counts like 45k/131k (34%)
5. Run openclaw status --usage — token usage data is similarly unavailable for omlx sessions

Expected behavior

• The context usage should display actual token counts (e.g., 📚 Context: 45,231/131,072 (34%)) based on the provider's usage field in the completion response
• Compaction count should increment correctly when auto-compaction triggers near the context limit
• The ? and (?%) placeholders should only appear when token tracking is genuinely unavailable, not when the provider returns valid usage data

Screenshots

N/A — the issue manifests as ? placeholders in the status display rather than a visual error.

Desktop (please complete the following information):

• macOS Version: 26.4.1
• oMLX Version: 0.3.8 (OpenClaw 2026.5.4, provider is a local MLX inference server on port 8200)

Additional context

The omlx provider is configured as a standard OpenAI-compatible endpoint (api: "openai-completions") pointing to a local MLX inference server. The model definition includes contextWindow: 131072 and maxTokens: 8192.

The issue likely stems from one of these:

1. The MLX server's completion response doesn't include a properly structured usage object (with prompt_tokens, completion_tokens, total_tokens fields) that OpenClaw expects from OpenAI-compatible APIs
2. OpenClaw's token counting logic doesn't handle the response format from this specific MLX backend correctly
3. The cost fields are all 0 (free/self-hosted), which may cause the token accounting pipeline to skip usage tracking entirely

The provider config looks like:

"omlx": {
  "baseUrl": "http://127.0.0.1:8200/v1",
  "apiKey": "omlx",
  "api": "openai-completions",
  "models": [{
    "id": "Qwen3.6-35B-A3B-UD-MLX-4bit",
    "contextWindow": 131072,
    "maxTokens": 8192,
    "cost": { "input": 0, "output": 0, "cacheRead": 0, "cacheWrite": 0 }
  }]
}

Other providers (mimo, volcengine, my-gpt) display token counts correctly, so this appears specific to the omlx/MLX provider path.