chenhg5/cc-connect · error

telegram: send image: %w

Error message

telegram: send image: %w

What it means

Platform.SendImage wraps errors from bot.SendPhoto with "telegram: send image: ". It means the photo upload/delivery to Telegram failed; the image bytes are streamed via InputFileUpload so large payloads and network faults are the usual causes.

Source

Thrown at platform/telegram/telegram.go:1153

		return fmt.Errorf("telegram: invalid reply context type %T", rctx)
	}
	bot, err := p.connectedBot("send image")
	if err != nil {
		return err
	}

	name := img.FileName
	if name == "" {
		name = "image"
	}
	slog.Debug("telegram: sending image", "chat_id", rc.chatID, "name", name, "size", len(img.Data))
	params := &tgbot.SendPhotoParams{
		ChatID:          rc.chatID,
		MessageThreadID: rc.threadID,
		Photo:           &models.InputFileUpload{Filename: name, Data: bytes.NewReader(img.Data)},
	}
	if _, err := bot.SendPhoto(ctx, params); err != nil {
		return fmt.Errorf("telegram: send image: %w", err)
	}
	return nil
}

func (p *Platform) SendFile(ctx context.Context, rctx any, file core.FileAttachment) error {
	rc, ok := rctx.(replyContext)
	if !ok {
		return fmt.Errorf("telegram: invalid reply context type %T", rctx)
	}
	bot, err := p.connectedBot("send file")
	if err != nil {
		return err
	}

	name := file.FileName
	if name == "" {
		name = "attachment"
	}

View on GitHub (pinned to 4000b2338a)

Solutions

  1. Check the wrapped cause for the real error (size limit vs network vs chat access)
  2. Resize/compress images to under 10 MB before SendPhoto, or send as a document instead
  3. Verify bot membership in the target chat and valid threadID
  4. Retry transient upload failures with backoff
  5. Validate img.Data is non-empty and a supported format (jpg/png/webp) before sending

Example fix

// before
if len(img.Data) > 10*1024*1024 { /* silently too large */ }
bot.SendPhoto(ctx, params) // fails
// after
if len(img.Data) > 10*1024*1024 {
    return p.SendFile(ctx, rctx, core.FileAttachment{Name: name, Data: img.Data})
}
_, err := bot.SendPhoto(ctx, params)
Defensive patterns

Strategy: validation

Validate before calling

// validate image before upload
if len(img.Data) == 0 {
    return errors.New("empty image data")
}
if len(img.Data) > 10*1024*1024 {
    return errors.New("image exceeds Telegram 10MB photo limit; send as document")
}

Try / catch

if err := p.SendImage(ctx, rc, img); err != nil {
    var apiErr *tgbot.Error
    if errors.As(err, &apiErr) {
        // inspect apiErr.Description for size/chat errors
    }
    return err
}

Prevention

When it happens

Trigger: bot.SendPhoto fails: multipart upload interrupted, image exceeds Telegram's 10 MB photo limit, invalid chat/thread ID, bot lacks access, or Telegram API returns an error.

Common situations: Sending screenshots or generated images larger than 10 MB (Telegram photo limit); flaky networks during multipart upload; bot removed from chat; sending to a topic thread that no longer exists.

Understand the failure class

Background: "API request failed": what wrapped HTTP errors from external APIs mean and how to find the real cause — this error's family across 29 libraries.

Related errors

AI-assisted analysis of chenhg5/cc-connect@4000b2338a (2026-09-06). Data as JSON: /api/errors/dede6241377e4a5e. Report an issue: GitHub.