I’d start with the built-in Salesforce node. If you need something more specific, I’d use an HTTP Request node with Salesforce credentials, and if you want event-based automation, I’d check the Salesforce Trigger node.
For the Claude piece, there’s a dedicated Anthropic Chat Model node in n8n’s AI section — no need for a raw HTTP Request since it handles the message structure automatically. For Salesforce auth, OAuth2 is definitely the way to go; credentials auto-refresh so you don’t get surprise token expiry mid-workflow. One thing worth watching on the Anthropic side: the default rate limits on lower tiers are tight for token-per-minute, so if you’re processing leads in a loop, add a short Wait node between iterations to avoid hitting the limit.