---
title: Place files
description: Give the agent the files an evaluation starts from.
---
> ## Documentation Index
> Fetch the complete documentation index at: https://docs.reeval.ai/llms.txt
> Use this file to discover all available pages before exploring further.

You set `files` on an environment to put source in the workspace before the agent starts. A destination path is relative to the workspace, uses forward slashes, and never contains `..`. To write into the home directory, start a path with `~/`.

## Write a file

Set `files` to an object of destination paths and contents. A string is written into the sandbox as that file.

In the `evals/environments.ts` file, define the environment:

```ts title="evals/environments.ts"
import { defineEnvironment } from '{{ pkg }}'

export const csv = defineEnvironment('csv', ({ directory, file }) => ({
  files: {
    ...directory('./project', { glob: ['!NOTES.md'] }),
    'data/people.csv': file('./data/people.csv'),
    '.gitignore': 'node_modules/\n',
  },
}))
```

The `.gitignore` entry writes that string to the workspace. For a runnable project, see [`with-fixture`](https://github.com/invertase/reeval/tree/main/examples/with-fixture).

## Copy a host file

When the content already exists on the host, pass a host path to `file`, as the `data/people.csv` entry does. A relative path resolves from the file that calls `file`. reeval uses an absolute path as given.

A destination that starts with `~/` goes in the home directory, outside the workspace and its diff:

```ts title="with-multi-turn.eval.ts"
files: {
  ...directory('./project'),
  '~/checks/call.mjs': file('./checks/call.mjs'),
},
```

## Copy a directory

Pass a host directory to `directory` to copy the files in it, as the `./project` entry does. Here `glob` leaves out the maintainer notes in `NOTES.md`.

To copy into a subdirectory, pass `into`, such as `directory('./fixtures', { into: 'src' })`. `into` is the destination directory. A value that starts with `~/` places the files under the home directory. `into` uses forward slashes and doesn't contain `..`.

By default, `directory` leaves out paths such as the `node_modules/` directory, and always leaves out the `.git` directory. A later entry in `files` replaces a copied file. For more information about pattern order, anchoring, and the default ignores, see [the directory helper](/reference/environment-helpers#directory).

## Reference

For more information about `file`, see [the file helper](/reference/environment-helpers#file).

For more information about `directory`, see [the directory helper](/reference/environment-helpers#directory).