Write once in Compose, fan out per platform, or schedule each natively. Every row below is generated from the same registry the publish worker reads; limits and content types are what the app actually enforces, not marketing copy.
Machine-readable version: GET /api/capabilities (JSON) · /llms.txt (agent-readable catalog). See the agent capabilities page for what an agent can do, not just where it can post.
Direct publish
Microblogging
XShort posts + articles · link previewsnotearticle280 char limit
TikTokShort-form vertical videosnote2,200 char limit · media required
PinterestVisual pins (images)notemedia required
InstagramVisual posts · carouselsnote2,200 char limit · media required
YouTube ShortsVertical video Shortsnote100 char limit · media required
More in the works
iMessageagent channel — planned, not available yetplanned
Each one is on the roadmap and goes live once the platform's own access or review step is done. The Settings → Platforms grid shows every one with its current connection state and exactly what stands between it and going live.