---

name: byted-tos-doc-process description: "Previews and exports documents stored in Volcengine TOS: generate PDF/PNG/JPG previews, read page counts, resolve HTML preview URLs, and batch-export PDF pages as images. Use this skill when the user needs to convert or preview office documents (Word, Excel, PPT, PDF), export specific pages as images, get document page counts, or generate HTML preview links — even if they don't explicitly mention 'doc-preview' or 'document conversion'." metadata: version: "1.0.0" openclaw: identity: - type: apikey provider: tos_provider env: - TOS_ACCESS_KEY - TOS_SECRET_KEY - TOS_ENDPOINT - TOS_REGION - TOS_BUCKET required: true optional: env: - TOS_OBJECT_KEY - TOS_SECURITY_TOKEN user-invocable: true license: Apache-2.0

Volcengine TOS Document Process

Preview and convert office documents stored in Volcengine TOS — PDF/PNG/JPG conversion, page count, HTML preview URL, and page-range export.

Setup (once per environment)

Install dependencies on first use:

cd {baseDir}
pip install -r {baseDir}/requirements.txt

Then run scripts with Python 3.7+:

python3 {baseDir}/scripts/<script>.py <args>

If you see a ModuleNotFoundError for tos, reinstall dependencies.

Environment Variables

This skill relies on the TOS identity declared in the metadata block. Common runtime variables are:

Environment Variable	Required	Description
TOS_ACCESS_KEY	Yes	TOS access key ID
TOS_SECRET_KEY	Yes	TOS secret access key
TOS_ENDPOINT	Yes	TOS endpoint URL
TOS_REGION	Yes	TOS region
TOS_BUCKET	Yes	Source bucket that stores the document
TOS_OBJECT_KEY	No	Source object key of the document. Can be overridden with --key
TOS_SECURITY_TOKEN	No	STS session token when using temporary credentials

Quick start (common tasks)

# Convert document to PDF
python3 {baseDir}/scripts/doc_preview_pdf.py --key report.docx --output preview.pdf

# Preview page 2 as PNG
python3 {baseDir}/scripts/doc_preview_png.py --key report.docx --page 2 --output page_2.png

# Preview page 2 as JPG
python3 {baseDir}/scripts/doc_preview_jpg.py --key report.docx --page 2 --output page_2.jpg

# Get total page count
python3 {baseDir}/scripts/doc_total_page.py --key report.docx --dest-type pdf

# Resolve HTML preview URL
python3 {baseDir}/scripts/doc_preview_html_url.py --key report.docx

# Batch export page range to TOS
python3 {baseDir}/scripts/doc_preview_process.py --key report.docx \
  --dest-type jpg --img-mode 1 --start-page 1 --end-page 3 \
  --saveas-bucket "output-bucket" --saveas-object "export/page_{Page}.jpg"

# Batch screenshot a PDF page range
python3 {baseDir}/scripts/doc_batch_screenshot.py --key test.pdf \
  --format png --start-page 1 --end-page 3 \
  --saveas-object "skill-test/doc/{Page}.png"

Available scripts

Script	Purpose
scripts/doc_preview_pdf.py	Convert document to PDF and save locally.
scripts/doc_preview_png.py	Render a single page as PNG.
scripts/doc_preview_jpg.py	Render a single page as JPG.
scripts/doc_total_page.py	Read total page count via x-tos-total-page header.
scripts/doc_preview_html_url.py	Resolve the final HTML preview URL (follows redirects and extracts tokens).
scripts/doc_preview_process.py	Generic doc-preview with full parameter control; supports TOS-to-TOS export.
scripts/doc_preview_params.py	Helper library to build x-tos-doc-* query parameters consistently.
scripts/doc_batch_screenshot.py	Batch-export PDF pages as images through doc-preview batch mode.

All scripts support --key to override TOS_OBJECT_KEY. Structured scripts also support --json for machine-readable output, and doc_preview_process.py / doc_total_page.py support --dry-run to preview the resolved request. Run any script with -h for full usage.

Out of scope

• Editing document contents (this skill is read-only preview/conversion).
• Generic object storage tasks unrelated to document preview.
• Local office conversion workflows that do not involve TOS.

Rules

• Authentication: Authentication is provided by the TOS identity declared in the metadata block above. Object selection can be overridden per script with --key.
• Pre-signed URL pattern: Document preview uses pre-signed URLs with x-tos-process=doc-preview and x-tos-doc-* query parameters, not the direct process keyword of get_object. Use doc_preview_params.py to build parameters consistently.
• Batch screenshot constraint: doc_batch_screenshot.py currently requires a PDF source object and persists results back to TOS with a {Page} placeholder.
• Save-as encoding: For doc-preview query-based save-as, the helper script automatically URL-safe-Base64 encodes x-tos-save-bucket and x-tos-save-object to match backend expectations.
• Custom domain note: For buckets created after Jan 03, 2024, online HTML preview may require a custom domain rather than the default TOS domain.
• Parameter source of truth: Official Volcengine TOS documentation is authoritative for the full doc-preview parameter matrix. When uncertain, check REFERENCE.md.
• Language: Reply in the user's preferred language.

Further reading

• Setup and environment: README.md
• Parameter reference: REFERENCE.md
• End-to-end workflows: WORKFLOWS.md