XCompose by Leander

XCompose adds lightweight AI writing controls directly to X's post and reply composers.

Choose Fix, Shorten, or Punchier from the XCompose menu. Additional actions include Expand, Formal, Casual, and Emojify. Rewrites replace the draft in place and can be undone.

Open Settings to choose OpenCode Go or OpenRouter, select a model, enable actions, and customize prompts. General instructions can apply to every rewrite. API keys and settings are stored locally in Firefox.

When you explicitly invoke an action, the selected draft and provider API key are sent over HTTPS to the provider you chose so it can generate the result. XCompose has no developer-operated backend, analytics, or advertising.

XCompose only runs on x.com and twitter.com. It does not read unrelated websites or send drafts to an AI provider until you invoke an action.