Workspaces for OpenAI Codex | Fast.io

Get started with Codex Desktop

Connect Fast.io to Codex Desktop with a custom MCP server.

1

Open MCP Server settings

Open Codex Desktop and go to Settings → MCP servers. Under Custom servers, click + Add server.

Codex Desktop Settings showing MCP Servers

2

Add a name and the MCP URL

Enter a name for the server (e.g. "fast-io"), select the Streamable HTTP tab, and paste the MCP URL below into the URL field.

https://mcp.fast.io/mcp

Codex Desktop Add MCP server configuration

3

Add a bearer token env var

In the Bearer token env var field, paste the variable name below. Remember this name, you'll use it in a later step. Click Save.

FAST_IO_MCP_TOKEN

Codex Desktop Bearer token env var configuration

4

Sign in to Fast.io

Go to go.fast.io and sign in or create a free account. Click your user icon in the bottom-left corner and select Account & Admin.

Fast.io user menu showing Account & Admin option

5

Navigate to API Keys

In the Settings sidebar, click API Keys under Devices & Agents. Then click Create API Key.

6

Name your API key

Give the key a descriptive name (e.g. "Codex Desktop Key") and click Create.

7

Copy your API key

Copy the API key now since it won't be shown again. Click the copy icon to save it to your clipboard, then click Done.

Fast.io API key created with copy warning

8

Set the environment variable

Open a terminal and run the command below (replace FAST_IO_MCP_TOKEN with the variable name you chose in step 3 if different). Paste the API key you just copied between the single quotes then press Enter.

launchctl setenv FAST_IO_MCP_TOKEN 'your
                                    API key'

Terminal running launchctl setenv command

9

Verify the connection

Restart Codex Desktop, then ask something like "can you see your fast.io account?" to confirm the connection is working. Codex should return your account details.

Codex Desktop showing Fast.io account details

Try these prompts

Copy and paste these into Codex to see Fast.io in action.

List all workspaces in this account

Create a new folder named "Images"

Give me a link to this newly created
                                        folder

Get started with Codex CLI

Add Fast.io to Codex CLI with a quick config edit.

1

Open the Codex config file

Open the Codex config file in a text editor (or create it if it doesn't exist). To edit with nano, for example, copy the text below and paste into your terminal.

nano ~/.codex/config.toml

2

Add the Fast.io MCP server config

Paste the config below into the file. This tells Codex where to find the Fast.io MCP server and which environment variable holds your API key. Exit nano by pressing Ctrl+X, then Y, and finally Enter to save.

[mcp_servers.fast-io]
url = "https://mcp.fast.io/mcp"
bearer_token_env_var = "FAST_IO_MCP_TOKEN"

Codex CLI config.toml with Fast.io MCP server config

3

Sign in to Fast.io

Go to go.fast.io and sign in or create a free account. Click your user icon in the bottom-left corner and select Account & Admin.

4

Navigate to API Keys

In the Settings sidebar, click API Keys under Devices & Agents. Then click Create API Key.

5

Name your API key

Give the key a descriptive name (e.g. "Codex CLI Key") and click Create.

6

Copy your API key

Copy the API key now since it won't be shown again. Click the copy icon to save it to your clipboard, then click Done.

7

Set the environment variable

Open a terminal and run the command below. Paste the API key you just copied between the single quotes then press Enter.

launchctl setenv FAST_IO_MCP_TOKEN 'your
                                    API key'

8

Start a new Codex CLI session

Run the command below to start Codex CLI. The Fast.io tools will be available automatically.

codex

9

Explore your Fast.io account

Ask Codex something like "can you see your fast.io account?" to get a summary of your profile, organization, plan details, and remaining credits.

Codex CLI showing Fast.io account summary

Try these prompts

Copy and paste these into Codex to see Fast.io in action.

List all workspaces in this account

Create a new folder named "Images"

Give me a link to this newly created
                                        folder

Everything your agents need to get work done

Give Codex a secure space to store, analyze, and share files alongside your team.

API

org-create-workspace

Create project-scoped storage with 50GB free. Intelligence mode auto-indexes files for RAG.

Files + Folders

workspace-storage-*

CRUD, move, copy, versions, locks, previews for 10+ formats. Chunked uploads up to 1GB.

Import

web-upload

Import files from any URL. OAuth support for Google Drive, OneDrive, Box, Dropbox. No local I/O.

Semantic Search

workspace-search

Find files by meaning, not keywords. "Show me contracts with indemnity clauses" works.

AI Chat (RAG)

ai-chat-create

Ask questions across entire workspaces. Auto-summarization, citations, metadata extraction.

MCP Server

mcp.fast.io

251 tools via Streamable HTTP or SSE. Session state persisted in Durable Objects.

Webhooks

webhook-create

Real-time notifications for file events. Build reactive workflows without polling.

Ownership Transfer

org-transfer-ownership

Build for humans, then hand off. Agent keeps admin access after transfer.

Shares & Data Rooms

share-create

Three modes: Send (deliver), Receive (collect), Exchange (collaborate). Password protection, expiration, branding.

Comments & Annotations

comments-*

Region-anchored feedback on images, timestamps on video/audio, page-specific on PDFs. Threaded replies.

$0/mo

Free forever. 50GB storage included. No credit card required.

50 GB

Cloud Storage

5,000

Monthly Credits

251

MCP Tools

Monthly credits cover storage, bandwidth, and AI operations. Resets every 30 days.

FAQ

What is the Fast.io MCP server?

It's a server that provides Codex with 251 workspace tools. By adding it to your config, Codex can upload files, create share links, and query documents using RAG.

How does authentication work?

The first time Codex uses a Fast.io tool, it opens a browser tab to sign in or create a free account. Your session persists, so there are no API keys to manage manually.

Can I see what Codex uploads?

Yes. Everything Codex stores is accessible at app.fast.io. You can browse, preview, comment on, and download files from any device.

Does this work with Codex CLI and Codex Desktop?

Yes. It works with both. For Codex Desktop, you add the MCP config in Settings. For Codex CLI, you add it to your ~/.codex/config.toml file.

What happens when I hit the credit limit?

You get 5,000 credits per month. When they run out, new uploads and AI queries pause until the next cycle. Existing files and share links remain accessible.

Can Codex share files with people who don't use Codex?

Yes. Share links are regular web URLs. Recipients open them in a browser and get previews, downloads, and commenting features without needing an account.

Workspaces for OpenAI

Get started with Codex Desktop

Open MCP Server settings

Add a name and the MCP URL

Add a bearer token env var

Sign in to Fast.io

Navigate to API Keys

Name your API key

Copy your API key

Set the environment variable

Verify the connection

Try these prompts

Get started with Codex CLI

Open the Codex config file

Add the Fast.io MCP server config

Sign in to Fast.io

Navigate to API Keys

Name your API key

Copy your API key

Set the environment variable

Start a new Codex CLI session

Explore your Fast.io account

Try these prompts

Everything your agents need to get work done

API

Files + Folders

Import

Semantic Search

AI Chat (RAG)

MCP Server

Webhooks

Ownership Transfer

Shares & Data Rooms

Comments & Annotations

FAQ

Give Codex a professional workspace