Synapsdex

Synapsdex is an AI writing assistant that lives inside X (Twitter) and helps you draft sharper replies, reposts and posts. You always review, edit and post everything yourself.

Open any post, pick an angle, and Synapsdex drafts ready-to-use options in seconds, grounded in the post you're actually looking at.

WHAT IT DOES
- Reads the post in front of you (text, metrics, community note) and drafts contextual replies — not generic filler.
- 12 strategic angles ("archetypes"): challenge it, build on it, fact-check it, make it funny, ask a sharp question, and more. Create unlimited angles of your own.
- 9 actions built in: Reply, Repost, Post, Counter, Question, TL;DR, Predict and more.
- Hooks generator: 5 scroll-stopping opening lines for your own posts.
- Personas: write in the style of a public figure whose name you type.
- Built-in filters: banned words and a reply-opportunity score to spend your time where it counts.
- Optional learning feature (in beta): studies the drafts you keep and edit to improve future suggestions over time.

TWO WAYS TO GENERATE
- Use your own AI API key (OpenAI, Anthropic and compatible providers) for the best quality.
- Or use the built-in no-key mode to start instantly.

SAFE BY DESIGN
- No automation that risks your account: it never auto-posts, auto-likes or auto-follows.
- No X API. It only reads what is on your screen and lets you paste drafts into X's composer yourself.
- Your settings and everything it learns stay on your device. Generation requests go only to the AI provider you chose.

Free to try, with a daily limit. A one-time purchase unlocks every archetype, every action and unlimited use.

Questions, feedback or feature requests? Join our Discord: https://discord.com/invite/hHcq8gewtD