File Write

The FileWriterTool is designed to write content to files.

FileWriterTool

Description

The FileWriterTool is a component of the crewai_tools package, designed to simplify the process of writing content to files with cross-platform compatibility (Windows, Linux, macOS). It is particularly useful in scenarios such as generating reports, saving logs, creating configuration files, and more. This tool handles path differences across operating systems, guards against path-traversal and symlink escapes, and creates parent directories (when a directory is explicitly provided) if they don’t exist, making it easier to organize your output reliably across different platforms.

The tool writes content in text mode — it is intended for plain-text files only (.txt, .md, .json, .yaml, .csv, .log, .py, config files, generated source, reports, etc.). It is not suitable for binary files such as images, PDFs, archives, or executables; writing binary data through it will raise or corrupt the output.

No explicit encoding is passed to open(), so the byte encoding follows locale.getpreferredencoding() — UTF-8 on Linux/macOS, but typically cp1252 on stock Windows. Set PYTHONUTF8=1 (or otherwise configure the locale) if you need guaranteed UTF-8 on Windows.

Installation

Install the crewai_tools package to use the FileWriterTool in your projects:

pip install 'crewai[tools]'

Example

The FileWriterTool is attached to an agent and invoked by that agent during a task — you don’t call it yourself. Initialize the tool, hand it to an Agent via tools=[...], and let the crew run.

Code

from crewai import Agent, Crew, Task, Process
from crewai_tools import FileWriterTool

# Initialize the tool
file_writer_tool = FileWriterTool()

# Define an agent that can write files
report_writer = Agent(
    role="Report Writer",
    goal="Produce written reports and save them to disk",
    backstory="A meticulous writer who files every report as a .md file.",
    tools=[file_writer_tool],
)

# Task that asks the agent to write a file
write_task = Task(
    description="Write a short markdown report summarizing the Q3 results to a file named q3_report.md inside the reports directory.",
    expected_output="Confirmation that q3_report.md was written to the reports directory.",
    agent=report_writer,
)

crew = Crew(
    agents=[report_writer],
    tasks=[write_task],
    process=Process.sequential,
)
result = crew.kickoff()
print(result.raw)

When the agent decides to write a file, it calls the tool with filename, content, and optionally directory and overwrite (see Arguments).

Arguments

• filename: The name of the file you want to create or overwrite.
• content: The text content to write into the file (string).
• directory (optional): The path to the directory where the file will be created. Defaults to the current directory (./). Parent directories are created only when directory is explicitly provided; the default ./ does not trigger directory creation.
• overwrite (optional, default False): Whether to overwrite an existing file. Accepts a bool or a string ("true"/"false", "yes"/"no", "1"/"0", etc.). When False, the tool opens in exclusive-create mode ("x") and returns an error if the file already exists; when truthy, it opens in write mode ("w") and replaces the file.

Conclusion

By integrating the FileWriterTool into your crews, the agents can reliably write content to files across different operating systems. This tool is essential for tasks that require saving output data, creating structured file systems, and handling cross-platform file operations. It’s particularly recommended for Windows users who may encounter file writing issues with standard Python file operations.

By adhering to the setup and usage guidelines provided, incorporating this tool into projects is straightforward and ensures consistent file writing behavior across all platforms.