openclaw - 💡(How to fix) Fix Weixin channel can drop standalone MEDIA directives when payload.mediaUrl is absent [1 comments, 2 participants]

Bug type

Behavior bug (incorrect output/state without crash)

Beta release blocker

No

Summary

For the openclaw-weixin channel, an assistant final reply that contains a standalone MEDIA:/path/to/image.png directive can be delivered as text only because the channel deliver() callback receives a payload without mediaUrl / mediaUrls.

This is different from #75182: the core MEDIA parser handles the directive correctly when tested directly, and there is no polluted-path ENOENT failure. The failure is that the final reply reaches the Weixin channel as text with mediaUrl=none.

Environment

• OpenClaw: 2026.5.5 (b1abf9d)
• Plugin: @tencent-weixin/[email protected]
• OS: Linux x64
• Node: v22.22.2

Steps to reproduce

1. Use the openclaw-weixin channel.

2. Send an assistant final reply containing a standalone local image MEDIA directive, for example:

   Here is a test image.
   
   MEDIA:/home/user/.openclaw/media/outbound/test.png

3. Observe the Weixin channel outbound logs and the WeChat client.

Expected behavior

The final reply MEDIA directive should be normalized to payload.mediaUrl / payload.mediaUrls before channel delivery, and the Weixin channel should upload/send the image.

Expected channel log shape:

outbound: ... mediaUrl=present
sendImageMessageWeixin: success ...
outbound: media sent OK ...

Actual behavior

The assistant final reply text contained the standalone MEDIA: line, but the Weixin channel logged mediaUrl=none and sent only text.

Relevant observed log shape:

outbound: ... textLen=57 mediaUrl=none
outbound: text sent OK ...

No sendWeixinMediaFile, upload, or sendImageMessageWeixin call occurred for that reply.

Debugging evidence

• Directly testing OpenClaw's MEDIA parsing on the same text returns the expected clean path in mediaUrls.

• Directly calling @tencent-weixin/openclaw-weixin's media-send helper with a 1MB PNG succeeds; the WeChat client receives the image.

• After adding a local fallback in the Weixin plugin deliver() path to parse standalone MEDIA: lines from payload.text when payload.mediaUrl is absent, the same normal assistant reply path succeeds:

  outbound: ... mediaUrl=present
  sendImageMessageWeixin: success ...
  outbound: media sent OK ...

This suggests the issue is at the OpenClaw core ↔ channel delivery contract boundary: core should consistently normalize reply directives before channel delivery, and/or the Weixin channel should defensively parse leftover standalone MEDIA: directives in payload.text.

Local workaround that fixed it

In @tencent-weixin/openclaw-weixin/src/messaging/process-message.ts, before markdown filtering in deliver(), parse standalone MEDIA: lines from rawText, remove them from the text body, and use the extracted path as a fallback:

function extractMediaDirectiveFromText(text: string): { text: string; mediaUrl?: string } {
  let mediaUrl: string | undefined;
  const keptLines: string[] = [];
  for (const line of text.split(/\r?\n/)) {
    const match = /^\s*MEDIA:\s*`?([^`\r\n]+?)`?\s*$/i.exec(line);
    if (match) {
      mediaUrl ??= match[1]?.trim();
      continue;
    }
    keptLines.push(line);
  }
  return { text: keptLines.join("\n").trimEnd(), mediaUrl };
}

// inside deliver(payload)
const rawText = payload.text ?? "";
const directiveMedia = extractMediaDirectiveFromText(rawText);
let text = (() => {
  const f = new StreamingMarkdownFilter();
  return f.feed(directiveMedia.text) + f.flush();
})();
const mediaUrl = payload.mediaUrl ?? payload.mediaUrls?.[0] ?? directiveMedia.mediaUrl;

With that local fallback, normal MEDIA: replies started delivering images correctly through Weixin.

Notes

There was also a separate edge case where a 154-byte tiny PNG caused a Weixin CDN status 500 during direct plugin upload, while a normal 1MB PNG uploaded and delivered successfully. That appears independent from this MEDIA directive normalization issue.