X (Twitter) API: Posts, Threads & Polls

API id: x

At a glance


Text	280 characters. 25,000 on accounts with a paid X subscription.
Links	Every link counts as 23 characters, whatever its real length.
Files per post	Up to 4
File needed?	No
Threads	Yes — up to 25 posts. Each reply can also have up to 4 files.
Alt text	Yes
Edit after publish	No
Delete after publish	Yes
Analytics	Impressions, likes, comments, shares, quotes, saves
Comments	Read replies from the last 7 days, and reply

Files

Type	Rules
Images (JPEG, PNG, WebP)	Up to 4 per post, 5 MB each.
GIF	1 per post, on its own, up to 15 MB.
Video (MP4)	1 per post, on its own. From 0.5 to 140 seconds. Shape between 1:3 and 3:1.

"On its own" means you cannot mix it with other files in the same post.

Options

Send these in channels[].options.

Key	Type	What it does
`poll_options`	list	2 to 4 poll answers, 25 characters each. A post with a poll cannot have files.
`poll_duration_minutes`	choice	How long the poll runs: `5`, `60`, `360`, `1440`, `4320` or `10080`. Default: 1 day.
`reply_settings`	choice	Who can reply: `following` or `mentionedUsers`. Accounts with a paid subscription can also use `subscribers` or `verified`. Default: anyone.

Example: a thread with a poll

{
  "channelId": "CHANNEL_X",
  "options": {
    "poll_options": ["Tabs", "Spaces"],
    "poll_duration_minutes": "1440"
  },
  "blocks": [
    { "content": "Settle this once and for all 👇" },
    { "content": "Results tomorrow." }
  ]
}

Good to know

A thread publishes one post at a time. If it stops halfway, a retry continues from where it stopped, without posting the first ones again.
To publish a thread, the account's continuationStatus on GET /channels must be available.

Comments

You can read the replies to a published post and answer them. See Read and reply to comments.

Only replies from the last 7 days. X's search, which Bulkit uses to find them, does not go further back. An older post can come back empty even if people replied.
Reading needs an X app access level that includes search. If yours does not, listing fails with a clear error. Replying still works.
100 replies per page. Use nextCursor for more.
You get replies to the post and the direct replies under them. Deeper replies, and replies under your own thread posts, are left out.
Newest first. When a reply's parent comment is on another page, the reply is listed on its own with parentId set to that comment.
Needs tweet.read and tweet.write, which every connected account already has.

Set up

To connect accounts, you first need your own app on this platform. See the X app setup guide.

Twitter / X