Composer

The composer is where you write posts. Open it with:

• New → Post in the sidebar;
• New post on the Publish page;
• + New on a free queue slot, or a click on the calendar, which opens it at that time.

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Write the post

Tick Create another to keep the composer open for the next post.

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Step 1: one shared editor

The first step is one editor for every selected network. Your text, media and links go to all of them.

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Step 2: one card per network

Customize for each network opens one card per network, in the same order as your channel list. Each card starts as a copy of the shared text, and you can change the text, media, Post Type and network settings for that network only. Pinterest, Discord and TikTok settings (board, channel, privacy) stay per account. Every other setting applies to all accounts of that network.

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Post types and network settings

Each network offers its own post types, such as Feed Post, Reel and Story on Instagram, or Post, Reel and Story on Facebook. On Pinterest and TikTok there is no post-type choice: the attached media decides it (a video makes a video pin or TikTok video, several images a Pinterest carousel, images alone a TikTok photo carousel). Some networks have extra settings: Instagram, TikTok videos, X and YouTube also offer the AI-generated switch: “Tell viewers your content was generated or edited with AI.” Each network has its own page under Platforms, for example TikTok and Google Business. YouTube: without a Title, the first non-empty line of your text becomes the title (up to 100 characters, without < or >). A post with no title and no text cannot be scheduled or published on YouTube.

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Character limits

The composer counts characters for each channel and warns before you save.

• Limits are per account. An X account with long posts (a Basic, Premium or Premium+ subscription, or a verified business) gets 25,000 characters instead of 280.
• No post can be longer than 25,000 characters, not even a draft.
• Every character counts once, emoji included.
• Mastodon’s content warning counts toward its 500 characters.
• Instagram allows up to 5 hashtags. The counter shows how many hashtags you have left.
• Instagram and Facebook Stories send no caption, so their text is not measured.

The network limits are checked when you schedule or publish, not when you save a draft. Each network’s limit is on its page in the Platforms section of the docs, for example X (Twitter) or Instagram.

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Threads of posts

On X, Bluesky and Mastodon you can publish a thread:

• Start thread adds a reply under the first post; Add to thread adds another.
• A thread has up to 24 replies.
• Each reply has its own text and media, and needs one of the two. Its media appears under that reply only.
• Each reply is measured against the account’s character limit.
• Press Shift Enter to start the next post of the thread, and Backspace in an empty one to remove it.

Other networks show “Threads of posts are not available on this network.”

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Link previews

When your text has a link, the composer shows a link preview card.

• The × (Remove link preview) publishes the post without the card. Facebook posts, Bluesky and LinkedIn honour it.
• Threads always shows a card for the first link, so it has no ×.
• Replace link preview with media adds the card’s image to the post as media.

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When it publishes

The queue options need posting times on every selected channel. If one has none, the composer says which (“No posting times:” followed by the channel names) and links to Manage posting times. See Queue. The option the composer starts with is your Default posting action in Preferences.

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Time zone

Times in the composer are shown in the composer zone, labelled next to the time:

• if every selected channel has the same time zone, that zone;
• otherwise, your own time zone from Preferences.

With exactly one channel selected, the date and time picker offers that channel’s posting times for the day, and greys out the ones another post already holds.

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Members who need approval

If your access is Needs approval, the save button reads Save and request approval. The post waits in Approvals instead of being scheduled or published.

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AI Assistant

The AI Assistant helps you write:

• Generate writes a post from a prompt (“What do you want to write about?”).
• Rephrase, Shorten, Expand, More casual and More formal rewrite your current text.

Then Insert, Replace your text, or Regenerate. The suggestion is tailored to the channel’s character limit. New text is written in your interface language; rewrites keep the language of your text. The assistant is part of the web app only; it is not available through the API or MCP.

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Also in the composer

• Templates opens your templates; picking one inserts its text.
• Insert a signature from the signature picker.
• Add labels to the post.
• Add emoji from the emoji picker in the toolbar.
• Expand dialog opens the composer full screen; Exit full screen brings it back.
• With no channel picked, Last used selects the channels you used last time; Select all picks every channel (Deselect all clears them).
• A file you remove stays under Suggested media until you close the composer, so you can add it back with one click.
• An empty editor says “Start writing or get inspired with Templates”; the link opens your templates.
• Post previews show each network’s version. “Previews are an approximation. Each network decides the final look of your post.”
• If you close the composer without saving, the next time you open it TryPost asks Resume unfinished post? Choose Resume post or Discard.

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API and MCP

The posting guide covers per-network settings, threads and scheduling modes over the API. See also the MCP tools reference.