Sendfile Skill

Send files to users in chat by creating a temporary public download link via aitun tunnel. Perfect for AI agents that need to deliver generated files (documents, images, reports, code) to users.

SendFile - Deliver Files to Users via Temporary Public Link

When to Use

Use this skill when:

• You generated a file (document, image, report, spreadsheet, code, etc.) and need to send it to the user
• The user asks to download a file you created
• You need to share a local file with the user in a chat conversation
• The chat platform does not support direct file uploads, or the file is too large
• You want to give the user a direct download link they can open in any browser

Do NOT use this skill when:

• The content can be displayed inline as text in the chat (just paste it)
• The file is already hosted at a public URL (share the existing URL instead)
• The file contains sensitive secrets or credentials (avoid exposing via public links)

Instructions

Step 1: Locate the file

Identify the file you want to send. This is typically a file you just generated:

• A document: .pdf, .docx, .pptx, .xlsx
• An image: .png, .jpg, .svg
• A code archive: .zip, .tar.gz
• Any other file the user requested

Verify the file exists:

ls -lh /path/to/your/file.ext

Step 2: Start a local file server

Start a simple HTTP server in the directory containing the file:

# If the file is at /path/to/output/report.pdf
cd /path/to/output
python3 -m http.server 8080 &
FILE_PID=$!
sleep 1

Step 3: Create a tunnel

Use aitun to expose the local server to the internet:

aitun -p 8080 &
AITUN_PID=$!
sleep 3

The output will contain the public URL, e.g.:

• https://aitun.cc/abc123

Step 4: Build the download link

Append the filename to the public URL to create a direct download link:

https://aitun.cc/abc123/report.pdf

Step 5: Send the link to the user

Deliver the download link to the user in the chat:

Your file is ready for download: https://aitun.cc/abc123/report.pdf

This link is temporary and will expire in 24 hours. Download it soon.

Step 6: Clean up

After the user confirms they have downloaded the file, stop the servers:

kill $AITUN_PID 2>/dev/null
kill $FILE_PID 2>/dev/null

CLI Reference

The aitun command (installed via pip install aitun) accepts these flags:

Flag	Description
-p PORT	Local service port (default: 8080)
-k TOKEN	Auth token for registered subdomain (omit for free tunnel)
--host HOST	Local service address (default: localhost)
--tcp-ports PORTS	TCP forwarding ports, comma-separated (e.g., 22,3306; requires -k)
--p2p	Enable P2P direct connection (default: enabled)
--no-p2p	Disable P2P, force server relay mode
--daemon	Run as background daemon
--stop	Stop running daemon

Notes

• Free tunnels use proxy address mode (path-based URL like aitun.cc/abc123), NOT subdomains
• Free tunnels expire after 24 hours, auto-renewed on restart
• Traffic can go through P2P direct connection or server relay, both are encrypted end-to-end
• For a permanent subdomain (e.g., files.aitun.cc), register at https://aitun.cc
• The download link works in any browser on any device — no installation required for the user
• Only one file server can run on the same port; if you need to serve files from different directories, use different ports