Quick start

$curl -fsSL https://fx.sh/setup.sh | bash

The installer places fx in ~/.local/bin. Read Installation before piping the script to a shell, or if fx is not on your PATH afterward.

$fx login

fx login opens the Vercel authorization flow and saves the session for later runs. An AI Gateway API key works too; see Authentication.

Run your first request

Start fx from the project you want to work on. The launch directory becomes the primary workspace:

$cd path/to/project

$fx

Type a request that names real files or commands, then press enter:

Read src/ and tell me how requests are routed. Then add a test for the
error path in the router and run the test suite.

fx streams its reply and shows the tools it runs. To redirect work already in progress, type a follow-up and press enter. Press escape to cancel, or ctrl+o to inspect the full transcript. Ctrl+c clears a nonempty draft; with an empty draft, it cancels the active turn.

What fx checks before it acts

fx starts in auto permission mode. It applies your saved rules, runs routine actions, and reviews actions that need a closer look. If the review raises a concern or cannot complete, fx holds the action and returns guidance to the agent.

Use ask mode if you want approval prompts for unresolved sensitive actions. Reading files within the workspace does not normally need approval; changing files, running commands, and accessing external paths are subject to the permission policy.

Switch modes with /permissions at any time, and see Permissions for rules, modes, and the cost of automatic review.

Approve deliberately

Read the scope shown in an approval prompt before accepting it. Full access mode disables fx permission checks; use it only in an environment you trust.

Things to know

In an interactive session, type / to open the available commands. See Slash commands for the full reference.

Need	Use
Open available commands	Type `/`
Find a file	Type `@`
Find a skill	Type `$`
Inspect the current model, workspace, permissions, and session	`/status`
Choose a model	`/models`
Change the permission mode	`/permissions`
Start a new session	`/new`
Attach an image	`/image ./path.png`
View local usage	`/usage`
Turn completion sounds on or off	`/sound on` or `/sound off`
Share feedback	`/feedback`
Create a private diagnostic trace	`/trace`

Every interactive command is listed in Slash commands.

Shortcuts

Action	Shortcut
Insert a newline	shift+enter, alt+enter, or backslash then enter
Move through prompt history	up or down at the edge of the draft
Steer the active turn with a follow-up	enter
Interrupt the current turn	escape, or ctrl+c with an empty draft
Open Review and Full transcript	ctrl+o, then left or right

Continue your work

Open the session picker to choose a saved session:

$fx -r

Resume the latest session for the current workspace directly:

$fx resume last