larksuite/cli · warning

invalid hex char at %d

Error message

invalid hex char at %d

What it means

decodeHex validates each character of the osascript «data ...» hex payload; when a character at position i is outside 0-9/a-f/A-F it reports the exact offset. Like the odd-length case, this is an intermediate parse error for clipboard image data; callers treat it as 'not an image' and continue.

Source

Thrown at shortcuts/doc/clipboard.go:200

	if len(s) >= 4 {
		s = s[4:] // skip class code, e.g. "HTML", "TIFF", "PNGf"
	}
	s = strings.TrimSuffix(s, "\xc2\xbb") // »
	s = strings.TrimSpace(s)
	return decodeHex(s)
}

// decodeHex decodes an uppercase hex string (as produced by osascript) to bytes.
func decodeHex(h string) ([]byte, error) {
	if len(h)%2 != 0 {
		return nil, fmt.Errorf("odd hex length") //nolint:forbidigo // intermediate decode helper; result discarded by caller on error
	}
	b := make([]byte, len(h)/2)
	for i := 0; i < len(h); i += 2 {
		hi := hexVal(h[i])
		lo := hexVal(h[i+1])
		if hi < 0 || lo < 0 {
			return nil, fmt.Errorf("invalid hex char at %d", i) //nolint:forbidigo // intermediate decode helper; result discarded by caller on error
		}
		b[i/2] = byte(hi<<4 | lo)
	}
	return b, nil
}

func hexVal(c byte) int {
	switch {
	case c >= '0' && c <= '9':
		return int(c - '0')
	case c >= 'a' && c <= 'f':
		return int(c-'a') + 10
	case c >= 'A' && c <= 'F':
		return int(c-'A') + 10
	}
	return -1
}

View on GitHub (pinned to 7fd6ef3c07)

Solutions

1. Copy an actual image (screenshot or copy-image in the source app) instead of copying text that contains the data wrapper.
2. Inspect the clipboard contents in a text editor and clear it (pbcopy < /dev/null) before retrying.
3. If you need to embed image data, use the proper file/upload flags of the command rather than the clipboard.

# Verify clipboard holds image data before running the command:
osascript -e 'clipboard info' | grep -q '«class PNGf»\|«class TIFF»' && echo ok || echo 'clipboard has no image data'

func isHexPayload(s string) bool {
    for i := 0; i < len(s); i++ {
        c := s[i]
        if !(c >= '0' && c <= '9' || c >= 'a' && c <= 'f' || c >= 'A' && c <= 'F') {
            return false
        }
    }
    return len(s)%2 == 0
}

if ! lark-cli doc import --clipboard; then
  echo "clipboard content is text, not an image; copy the image itself and retry" >&2
fi

When it happens

Trigger: The macOS clipboard holds an «data XXXX...» literal whose payload includes non-hex characters — typically because the clipboard actually contains text (a doc snippet or base64 string) rather than binary image data captured by osascript.

Common situations: Copying a data-URI example (base64 contains characters like '+', '/', '=') from docs and running a command that expects a clipboard image; clipboard apps transforming the payload.

Related errors

• odd hex length
• keychain access blocked

AI-assisted analysis of larksuite/cli@7fd6ef3c07 (2026-09-04). Data as JSON: /api/errors/e13839fe4502382a. Report an issue: GitHub.