anthropics/skills · error · RuntimeError

PDF conversion failed: {detail}

Error message

PDF conversion failed: {detail}

What it means

Raised when converting a PPTX to PDF via LibreOffice (`soffice --headless --convert-to pdf`) either exits non-zero or produces no output PDF. The message appends LibreOffice's stderr/stdout as detail. It means the external soffice process itself failed or silently produced nothing.

Source

Thrown at skills/pptx/scripts/thumbnail.py:198

    img = Image.new("RGB", size, color="#F0F0F0")
    draw = ImageDraw.Draw(img)
    line_width = max(5, min(size) // 100)
    draw.line([(0, 0), size], fill="#CCCCCC", width=line_width)
    draw.line([(size[0], 0), (0, size[1])], fill="#CCCCCC", width=line_width)
    return img


def convert_to_images(pptx_path: Path, temp_dir: Path) -> list[Path]:
    pdf_path = temp_dir / f"{pptx_path.stem}.pdf"

    result = run_soffice(
        ["--headless", "--convert-to", "pdf", "--outdir", str(temp_dir), str(pptx_path)],
        capture_output=True,
        text=True,
    )
    if result.returncode != 0 or not pdf_path.exists():
        detail = (result.stderr or result.stdout or "").strip()
        raise RuntimeError(f"PDF conversion failed: {detail}" if detail else "PDF conversion failed")

    result = subprocess.run(
        [
            "pdftoppm",
            "-jpeg",
            "-r",
            str(CONVERSION_DPI),
            str(pdf_path),
            str(temp_dir / "slide"),
        ],
        capture_output=True,
        text=True,
    )
    if result.returncode != 0:
        raise RuntimeError("Image conversion failed")

    return sorted(temp_dir.glob("slide-*.jpg"))

View on GitHub (pinned to f6656c1256)

Solutions

1. Run `soffice --headless --convert-to pdf --outdir /tmp test.pptx` manually and read the stderr echoed in the message
2. Install LibreOffice (e.g. `apt-get install -y libreoffice` on Debian/Ubuntu) or add it to the CI image
3. Clear a stuck profile lock: delete ~/.config/libreoffice/4/user/.lock or run with `-env:UserInstallation=file:///tmp/lo_profile`
4. If the file is corrupt/unopenable, repair or regenerate the PPTX before thumbnailing

Example fix

// before
result = run_soffice(["--headless", "--convert-to", "pdf", "--outdir", str(temp_dir), str(pptx_path)], capture_output=True, text=True)
// after: isolated profile avoids the single-instance/profile-lock failure mode
result = run_soffice([
    "--headless",
    "-env:UserInstallation=file:///tmp/lo_thumb_profile",
    "--convert-to", "pdf",
    "--outdir", str(temp_dir),
    str(pptx_path),
], capture_output=True, text=True)

import shutil
from pathlib import Path

def can_convert_pptx(pptx_path: Path) -> tuple[bool, str]:
    if shutil.which("soffice") is None:
        return False, "LibreOffice (soffice) not on PATH"
    if not pptx_path.is_file() or pptx_path.stat().st_size == 0:
        return False, f"missing or empty file: {pptx_path}"
    return True, ""

try:
    images = convert_to_images(pptx, tmp)
except RuntimeError as e:
    log.error("thumbnail pipeline failed: %s", e)  # message embeds soffice stderr
    raise ThumbnailUnavailable(pptx) from e

When it happens

Trigger: Calling convert_to_images(pptx_path, temp_dir) when: LibreOffice is not installed or `soffice` is not on PATH; the .pptx is corrupt/password-protected so LibreOffice aborts; a stale soffice profile lock prevents headless startup; the expected output file temp_dir/{stem}.pdf was not created even though returncode was 0.

Common situations: CI containers without libreoffice installed; first-ever headless run after a crashed LibreOffice leaves a locked user profile (~/.config/libreoffice/4/user/.lock); running while another soffice instance is starting; filenames with characters LibreOffice mangles so the produced PDF name differs from {stem}.pdf.

Related errors

• LibreOffice rendered {len(visible_images)} page(s) for {visi
• Image conversion failed
• 1
• relationship target is not a POSIX part name: {target!r}
• relationship target escapes the package: {target!r}

AI-assisted analysis of anthropics/skills@f6656c1256 (2026-08-14). Data as JSON: /api/errors/7c808fc9db1248bc. Report an issue: GitHub.