For setup, see relay2ts
- Takes a Relay component, and converts its Relay fragment into an interface for your Component's props.
As this isn't in the extensions section of VS Code:
git clone https://github.com/alloy/vscode-relay.git
cd vscode-relay
yarn install
yarn global add vsce
vsce package
code --install-extension vscode-relay-0.0.1.vsix