What is whathappened?

whathappened is an agent skill built specifically for Grok Build, the coding agent from xAI. It answers a simple question, what just happened on X and what is the conversation actually saying about it, by pulling from X's own search and thread tools rather than a general web search or a blog roundup. When you run the skill on a topic, it produces a short, structured briefing rather than a wall of raw posts. The output includes a plain summary of the event, a description of where the conversation is happening and who is loudest, an opinion map that breaks reaction into rough camps with estimated shares and representative accounts, a list of the live disagreements people are having about the topic, and links back to the specific posts used as evidence. It also adjusts its time window on its own: fast moving breaking news gets a window of minutes to hours, while quieter or still developing stories get a wider window so the picture is more complete. The README is upfront that this only works inside Grok Build, because it depends on four of Grok's built in X tools for keyword search, semantic search, thread fetching, and user search. If a user installs the skill into a different agent, such as Claude Code, Cursor, or Codex, they can view the package but the skill will not actually be able to produce a real briefing, since those tools are not available there. The skill is designed to refuse rather than fake a result if those tools are missing. Installation is a single command using the skills package manager, either globally or per project, or by copying the skill folder directly into Grok's skills directory. Internally, the process resolves who or what the topic refers to with at most one optional web lookup, measures how fast the story is moving to decide the time window, runs a set of X searches across different modes, and then fetches threads to identify the original source, official statements, and the different camps in the debate.