Tumblr: posting rules and settings

What a Tumblr channel accepts in Postemi: media, limits, required fields, and the fields of the settings object for the API.

Basics

Rules

• You pick the blog when you connect. Each blog is its own channel.
• Long text is split into blocks of 4096 characters.
• Beta: not yet tested with many accounts.

Settings fields

These fields go into the post's settings object, alongside the __type field. In the UI, you fill in the same ones in the channel's settings section.

Examples

Each example is one item in the POST /public/v1/posts request's posts array. The envelope around it is always this:

{
  "type": "schedule",
  "date": "2026-09-15T09:00:00.000Z",
  "shortLink": false,
  "posts": [ /* the item below */ ]
}

{
  "integration": { "id": "<channel-id>" },
  "value": [{ "content": "<p>The text of the post.</p>", "image": [] }],
  "settings": { "__type": "tumblr" }
}

The channel ID comes from the channel list, and the path values for images and videos from media upload. The exact schema for the connected account comes from the settings schema endpoint. From the command line, the same thing is the --settings flag. See the CLI examples.