# Overview
<subtitle>Read, write, upload, and download files in the sandbox, and monitor file system changes. </subtitle>

Each UCloud Sandbox has its own, isolated file system.

Using UCloud Sandbox SDK you can:
- [Read and write files in the sandbox. ](/docs/agent-sandbox/filesystem/read-write.md)
- [Get file or directory information. ](/docs/agent-sandbox/filesystem/info.md)
- [Append custom metadata to the file. ](/docs/agent-sandbox/filesystem/metadata.md)
- [Listen for directory changes. ](/docs/agent-sandbox/filesystem/watch.md)
- [Upload data to sandbox. ](/docs/agent-sandbox/filesystem/upload.md)
- [Download data from sandbox. ](/docs/agent-sandbox/filesystem/download.md)

> The disk usage of the sandbox will be included in the storage usage and billed according to rules. For details, please refer to [Billing Instructions](/docs/agent-sandbox/product/fee.md).

## Basic usage

```python
from ucloud_sandbox import Sandbox

sandbox = Sandbox.create()

#Write to file
sandbox.files.write("hello.txt", "UCloud Sandbox is awesome!")

#Read file
content = sandbox.files.read("hello.txt")
print(content) # Output: UCloud Sandbox is awesome!

# List directories
files = sandbox.files.list("/home/user")
for f in files:
    print(f.name, f.type)

sandbox.kill()
```

> **Default working directory**: Most file operations are performed under `/home/user` by default. Use absolute paths to access anywhere on the file system.