Summary

When Feishu channel streaming is enabled with card render mode, replies show an abnormal typewriter effect (1-2 characters at a time) and the final card content is truncated — often leaving only the last character (e.g. "？"), with all other text lost.

Environment

• OpenClaw version: 2026.5.28 (also reproduced on 2026.5.27)
• Feishu plugin: @openclaw/[email protected]
• Model: deepseek/deepseek-v4-flash
• Agent: main
• Deployment: Tencent Cloud Lighthouse, Ubuntu, Feishu websocket
• Feishu client: Both mobile & desktop — same issue

Configuration

"feishu": {
  "enabled": true,
  "appId": "cli_a968b21595b89bdf",
  "streaming": true,
  "renderMode": "card",
  "blockStreaming": false,
  "textChunkLimit": 8000
}

Steps to Reproduce

1. Set channels.feishu.streaming: true
2. Set renderMode: "card"
3. Set blockStreaming: false
4. Send a message via Feishu DM that triggers a longer reply (tool call + summary, or multi-paragraph text)
5. Observe the streaming card during generation and the final card content

Expected Behavior

• Smooth typewriter streaming effect on Feishu card
• Final card shows complete reply content
• Tool call output and final summary are both visible

Actual Behavior

• Typewriter effect is abnormal (characters appear 1-2 at a time, not smooth streaming)
• Final card content is truncated; only the last few characters remain (often just "？")
• Intermediate streaming may show partial text, but final rendered card loses most content

Control Groups

Workaround

"feishu": {
  "streaming": false,
  "renderMode": "card",
  "blockStreaming": false
}

Content is complete but without typewriter effect.

Additional Notes

• Issue present since 2026.5.27, still unfixed in 2026.5.28
• Changelog does not mention Feishu streaming fixes for this behavior
• Possibly related to CardKit streaming card update/finalize race (partial → idle → final)
• Gateway log snippet (dispatch to close: ~9s, close happens ~7s after dispatch complete):

feishu[default] Started streaming: cardId=7646292918105738171
feishu[default]: dispatch complete (queuedFinal=true, replies=1)
feishu[default] Closed streaming: cardId=7646292918105738171

Related Issues

• Feishu streaming card produces duplicate/truncated messages with long replies #65993 — streaming card duplicate/truncation (partially fixed)
• [Bug]: Feishu CardKit streaming card appends full accumulated text on each update instead of replacing #82417 / PR fix(feishu): stream CardKit text deltas #82419 — CardKit full-text append duplication
• [Bug]: Feishu/Lark: streaming card sessions are created even when channels.feishu.streaming=false (final message may show only tail / truncated) #10078 — streaming=false still creates streaming card, final content truncated
• Feishu streaming card duplicates on long responses (飞书流式卡片长回复重复) #75757 — long replies produce duplicate streaming cards
• PR fix(feishu): prevent duplicate message after streaming card close (#67791) #68491 — onPartialReply→onIdle→final race fix (not merged)

Attachments

Screenshot of final truncated Feishu card (showing only "？") will be added as a comment after issue creation.