Creating posts
How to create and publish content.
Tell your assistant things like:
The assistant uses the postCompose tool after you choose or approve the exact caption. It can help you draft first in chat, but it should not create, schedule, or publish a post until the caption is confirmed. For a generated image or video that should become a post immediately, the preferred tool is postCompose. It uploads the media and creates the draft or scheduled post in one step.
ChatGPT sandbox paths such as /mnt/data/... are not public URLs. The assistant must send the actual media bytes as base64 for small files, or use mediaPrepare for larger files. Local MCP runtimes can pass a filePath to stream a binary multipart upload from disk, but hosted ChatGPT connectors still need bytes or a direct upload URL. Use mediaPrepare when you only want to add media to the library for later reuse.
Once created, your posts appear in the Posts tab and the Calendar on the dashboard.