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)
Prerequisites
Install the aitun client (any one of):
# Install via pip (recommended, cross-platform, bundles the binary)
pip install aitun
# Or one-line install script (Linux/macOS)
curl -fsSL https://aitun.cc/install.sh | bash
# Windows (PowerShell)
irm https://aitun.cc/install.ps1 | iex
Verify the install:
which aitun
aitun --help
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, or alternatively curl -fsSL https://aitun.cc/install.sh | bash / irm https://aitun.cc/install.ps1 | iex on Windows) accepts these flags:
| Flag | Description |
|---|---|
-p PORT |
Local HTTP service port (optional; omit for TCP-only mode with --tcp-ports) |
-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). Use without -p for TCP-only mode |
--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