Auto-DM is for messages people ask for. From today, every Auto-DM needs a keyword: only someone who replies to the post with that word gets the message. A reply without it, a repost on its own, or anything that happened before the campaign started doesn't count.
You can still ask for more on top of the reply, such as a repost or a follow, and the message, variables and window are unchanged.
A campaign set up before today without a keyword pauses itself and says so on the post's Auto-DM card. Give it one over the API (PATCH /api/v1/auto-dms/{id} with replyKeyword, plus triggers: ["reply"] or match: "all" where the card's note asks for them) or the SDK's autoDms.update, and it picks back up. Nobody already messaged is messaged again, and anyone it was still waiting on has to reply with the keyword like everyone else.
AI agents connected over MCP can still put an Auto-DM on a post they draft, but the tools for starting, changing and stopping campaigns have been removed: sending direct messages in your name is a decision for a person. The MCP tools that publish straight away now take your explicit go-ahead before anything is sent.