How to schedule YouTube videos and Shorts

When the time comes, the scheduler opens a resumable upload session with YouTube, sends the title, description, tags, visibility and the made-for-kids answer, then streams the video file in parts. A resumable upload matters for large files: if the connection drops halfway, the upload continues from the last part YouTube received instead of starting again. Nothing appears on your channel until the last byte arrives, so a failure before that point leaves no half-finished video behind.

Once YouTube has the file, it still has to process it. A video can be live on the channel and show only in low resolution for the first minutes while the higher resolutions are encoded. That is normal and not a failed post.

• Export an MP4. A YouTube post in Hookpost takes exactly one media item and it must be a video; an image, a GIF or two files are refused before scheduling with "You need one media" or "Item must be a video".
• For a regular video, use 16:9, such as 1920x1080. For a Short, export vertical 9:16, such as 1080x1920. YouTube also treats square videos as Shorts.
• Keep a Short at three minutes or less. Anything longer is published as a regular video, however it is framed.
• Mix the sound to a sensible loudness and check the first second. The first frame is what people see if the thumbnail cannot be set, and a fade from black makes a black thumbnail.
• Check the file plays from start to end on your own machine. "The video file is missing or could not be read, please re-upload the video." usually means a broken export or an upload that never finished.

YouTube has hard limits here, and a scheduler that checks them before queueing saves you a failed upload at night.

• Title: required, up to 100 characters. Hookpost asks for at least 2. Put the words people would search for first, because the end of a long title is cut off in search results and on phones.
• Description: up to 5,000 characters. YouTube rejects descriptions containing the characters < or >, with the error "Your video description is invalid, it may contain disallowed characters such as < or >." Write arrows and comparisons out in words.
• Links: put the most important link in the first two lines of the description, since only those show before "more".
• Tags: the total length of all tags is capped at 500 characters. A tag that contains a space is wrapped in quotes by YouTube, and those two quote marks count toward the 500. Ten precise tags are worth more than forty loose ones.
• Hashtags: a few hashtags at the end of the description are fine. For a Short, adding #Shorts to the title or description is common practice, but the format and length are what make a video a Short.

Every upload needs a visibility setting: public, unlisted or private. Unlisted is useful for a video you want to embed on your own site or send to a few people without it appearing on the channel or in search. Private is for checking the upload before anyone sees it; you can make it public later in YouTube Studio.

Every upload also has to say whether the video is made for children. This is a legal declaration under YouTube's rules, not a targeting option. Answering yes turns off comments, notifications and personalised ads on that video, so answer it honestly for each video rather than leaving a default on.

A custom thumbnail is set after the video exists, as a second step. Use a JPEG or PNG at 1280x720 and keep it under 2 MB. YouTube refuses custom thumbnails on channels that have not completed phone verification. In that case the video is still published, and Hookpost reports it as a warning: "Your account is not verified, we have uploaded your video but we could not set the thumbnail. Please verify your account and try again." Verify the channel once in YouTube's settings and the thumbnail step works from then on.

Other thumbnail messages are also warnings on a video that did upload: "the thumbnail format is not supported, please use JPEG or PNG", "the thumbnail image is too tall" or "too wide", and "Thumbnail size is too large". Fix the image and set it in YouTube Studio; do not upload the video again, or you will have two copies.

• Cut all the Shorts first, each from a different moment, and give each its own title. Repeating the same title on every Short makes them hard to tell apart in your own analytics.
• Post one a day at the same hour rather than several at once. Viewers who find one Short then find a channel that keeps posting, and each Short gets its own day to be shown.
• Pick the hour from your own audience data in YouTube Studio once you have some; until then, early evening in your main audience's time zone is a reasonable start.
• Put the same one or two links in every description, so a viewer who likes any of them can find the full video or your site.
• After the first one goes out, open it on a phone to check the framing and the first second before the rest publish.

These are the messages YouTube's responses map to in Hookpost, and what to do about each:

• "Token expired or invalid, please reconnect your YouTube account." The connection has lapsed or access was removed in your Google account. Reconnect the channel; the post can then be retried.
• "YouTube refused the upload for this channel. Make sure the Google account you connected with can upload to this channel, then reconnect it." Common with brand accounts: the Google account you signed in with is not an owner or manager of the channel you picked.
• "You have to link your youtube account to your google account first." The Google account has no YouTube channel yet. Create the channel in YouTube, then connect again.
• "You have reached your daily upload limit, please try again tomorrow." YouTube limits how many videos a channel can upload in a day. Spread the queue over more days.
• "You are sending requests too quickly, please wait a little while and try again." Space out uploads to the same channel.
• "Some of the video details are invalid, please review the title, description and tags." Check the limits above, especially the tag total.

Google restricts videos uploaded through API projects that have not passed its audit: such uploads are locked to private. If you write your own script against the YouTube Data API, expect your test uploads to be private until the project passes that audit. Through Hookpost, uploads publish with the visibility you choose.

Hookpost's YouTube integration: its validation rules (one MP4, title 2 to 100 characters, 500-character tag total, description limit) and the error messages it maps YouTube's responses to, read from its code on 13 November 2026, and the videos and Shorts we schedule through it. Hookpost is a product of the same team as HookStep.

• YouTube Data API: Videos: insert, read 13 November 2026.

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