Quickstart: Codex

Codex connects to Probably's remote MCP server at https://studio.probably.co/api/mcp, configured in ~/.codex/config.toml. Sign in with OAuth at your machine, or read an API key from an environment variable in CI and other places without a browser.

Connect with OAuthCopy Anchor Link

Add the server to ~/.codex/config.toml:

[mcp_servers.probably]
url = "https://studio.probably.co/api/mcp"

Then sign in:

codex mcp login probably

Your browser opens Probably's sign-in and a consent page, where you choose the organization, optionally one Space, and whether Codex may start paid work after you confirm it in the chat.

Or connect with an API keyCopy Anchor Link

Create a key in Settings → Connections (see Authentication), and tell Codex which environment variable holds it:

[mcp_servers.probably]
url = "https://studio.probably.co/api/mcp"
bearer_token_env_var = "PROBABLY_API_KEY"

export PROBABLY_API_KEY="prb_..."
codex

Codex sends the key as a Bearer token on every call; it never needs the browser. This is the way to use Probably from codex exec in CI.

To check the key outside Codex, set the API's address and your key, then ask the server which tools it offers:

export PROBABLY_API_URL="https://studio.probably.co"
export PROBABLY_API_KEY="prb_..."

#!/usr/bin/env bash
# Ask the MCP server which tools your API key is offered, as an MCP client
# set up with an Authorization header does.
set -euo pipefail

curl --silent --show-error --fail-with-body \
  --request POST "$PROBABLY_API_URL/api/mcp" \
  --header "Authorization: Bearer $PROBABLY_API_KEY" \
  --header "Content-Type: application/json" \
  --header "Accept: application/json, text/event-stream" \
  --data '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

Make your first videoCopy Anchor Link

Ask Codex to list your Spaces, then to prepare a video from a brief in one of them. It shows you the preview from prepare_video; once you agree, it calls confirm_spend, and wait_for_video tells it when the video changes. Every tool is in the MCP tool reference.