Open File with OS Default Application

Open File with OS Default Application

Open any file on disk using the operating system's default application for viewing.

When to Use This Skill

Use this skill when the user wants to:

• Open a file that already exists on disk
• Preview a document, image, PDF, or spreadsheet
• View a file with the default application
• Display a file that has already been saved

Trigger phrases:

• "Open the file contract.pdf"
• "Show me the document in _RESULTS_FROM_AGENT/​report.docx"
• "Preview the image logo.png"
• "View this spreadsheet"
• "Display the PDF I downloaded earlier"
• "Open the email attachment"

Do NOT use this skill if:

• The file needs to be downloaded from the database first (use bel-download-file-from-crm-db instead)
• The user wants to view a file from the database (use bel-show-crm-file instead)
• The file doesn't exist on disk yet

How to Use This Skill

Quick Start

Simply execute the script with the file path:

python scripts/​open_file.py <file_path>

Examples:

# Open a PDF
python scripts/​open_file.py _RESULTS_FROM_AGENT/​contract.pdf

# Open an image
python scripts/​open_file.py _DATA_FROM_USER/​logo.png

# Open a spreadsheet
python scripts/​open_file.py _RESULTS_FROM_AGENT/​report.xlsx

# Open an email file
python scripts/​open_file.py _DOWNLOADS_FROM_AGENT/​message.eml

# Quiet mode (suppress output)
python scripts/​open_file.py document.pdf --quiet

Supported File Types

The script works with any file type that has a registered default application on the operating system:

Documents:

• PDF: .pdf
• Word: .docx, .doc
• Text: .txt, .md, .log
• Rich Text: .rtf

Spreadsheets:

• Excel: .xlsx, .xls, .csv
• Numbers: .numbers

Images:

• Common formats: .png, .jpg, .jpeg, .gif, .bmp, .svg
• Professional formats: .tif, .tiff, .webp

Emails:

• Email messages: .eml, .msg
• Outlook: .pst

Archives:

• Compressed files: .zip, .tar, .gz, .7z

Presentations:

• PowerPoint: .pptx, .ppt
• Keynote: .key

And many more! If the OS has a default application registered, this skill will open it.

Cross-Platform Support

The script automatically detects the operating system and uses the appropriate command:

macOS:

• Command: open <file>
• Opens files with the default macOS application

Linux:

• Command: xdg-open <file>
• Opens files with the default Linux desktop application

Windows:

• Command: os.startfile(<file>)
• Opens files with the default Windows application

Technical Details

How It Works

1. Validates that the file exists on disk
2. Resolves to absolute path for reliability
3. Detects the operating system
4. Executes the appropriate OS command to open the file
5. Returns success/​error status

Error Handling

Common errors:

• File not found: The specified file path doesn't exist
• Permission denied: Insufficient permissions to access the file
• No default application: No application registered for that file type
• Command not found: xdg-open not available on Linux (rare)

Integration with Other Skills

This skill integrates with:

• bel-download-file-from-crm-db: First download, then open
• bel-show-crm-file: Orchestration skill that uses both download and open
• Any skill that produces output files that need to be viewed

Example Workflows

Workflow 1: Open a specific file

User: "Open the contract.pdf file"

1. Verify file exists at specified path
2. Run: python scripts/​open_file.py contract.pdf
3. File opens in default PDF viewer

Workflow 2: Preview downloaded results

User: "Show me the report I generated"

1. Identify the file path (e.g., _RESULTS_FROM_AGENT/​report.xlsx)
2. Run: python scripts/​open_file.py _RESULTS_FROM_AGENT/​report.xlsx
3. File opens in default spreadsheet application

Workflow 3: View user-provided data

User: "Display the image I uploaded"

1. Find the image in _DATA_FROM_USER/
2. Run: python scripts/​open_file.py _DATA_FROM_USER/​logo.png
3. Image opens in default image viewer

Notes on Email Files

Email files (.eml, .msg) work well with this skill:

• .eml files: Standard email format, opens in default mail client (Mail.app on macOS, Outlook on Windows, Thunderbird on Linux)
• .msg files: Outlook format, opens in Outlook or compatible email client

The operating system handles the rendering and display automatically.