PostFast MCP Server for Claude, ChatGPT and Cursor: Launch Notes and Changelog (2026)

PostFast has had a public REST API since May 2025, an MCP server on npm since March 1, 2026, and hosted connectors for ChatGPT and Claude since June 5, 2026. This post is the launch note we never wrote at the time, plus the changelog since: what the server does, how the two ways to connect differ, and what the main releases added. Everything below was checked against the npm publish history, PostFast's roadmap and the integration pages in September 2026.

What it is

An MCP server lets an AI assistant call a product's functions directly. With PostFast connected, Claude, ChatGPT or Cursor can list your social accounts, draft and schedule posts to 11 platforms, upload media, read post analytics and follower history, and work the comment inbox, all in plain language and all on your real PostFast account.

Two ways to connect, same account:

Both are included on every plan, including the 7-day trial, with no per-seat and no per-conversation charge.

Timeline

• May 7, 2025: REST API. Schedule content to every supported platform programmatically, with an API key per workspace. Documented at postfa.st/docs.
• March 1, 2026: postfast-mcp 0.1.0 on npm. The first release, documented for Claude Code and authenticated with the API key, with nine tools: accounts, list, create and delete posts, Pinterest boards, YouTube playlists, connect links and two media upload tools, across 10 platforms. Claude Desktop, Cursor and the other clients arrived in later point releases.
• June 5, 2026: ChatGPT and Claude connectors. The hosted connector at mcp.postfa.st signs in over OAuth, so there is no key to paste. Draft, schedule and review posts without leaving the chat.
• August 5, 2026: postfast-mcp 0.2.0. One shared tool catalog for the local server and the hosted connector, and three hosted-only tools: approve posts, list workspaces and upload from a URL.
• August 5, 2026: postfast-mcp 0.3.0, the Social Inbox tools. Comments from TikTok, Instagram, Facebook Pages and Threads in one inbox that an assistant can read, reply to, hide, assign and triage, including Instagram private replies.
• August 8, 2026: postfast-mcp 0.4.0. TikTok sounds: list trending Commercial Music Library tracks and attach one to a photo carousel (TikTok Business accounts).
• August 14, 2026: postfast-mcp 0.5.1 to 0.5.3. Tool annotation corrections, and output schemas removed after Claude's desktop client started rejecting them.
• August 24, 2026: postfast-mcp 0.6.0, the current release: connect links gained platform, redirect URL and external ID options. Point releases 0.1.1 to 0.1.24 shipped between March and July.

What an assistant can do today

• Plan and draft: list accounts and their connection status, list posts, save drafts, hold posts for approval (approving is a hosted-connector tool).
• Schedule and publish: up to 15 posts per request, with platform options in words: Reel or feed post, TikTok direct publish or draft, YouTube title and privacy, a Pinterest board, a LinkedIn document post, a Google Business Profile event with a call-to-action button.
• Attach media: upload a file, an image from the chat, or a URL through the hosted connector; videos up to 250 MB, images up to 10 MB.
• Measure: post analytics per published post where the platform exposes them, and follower history per account.
• Answer comments: list conversations, reply publicly, send an Instagram private reply, hide or delete a comment, mark read, assign to a teammate.

Connect in two minutes

• ChatGPT: Settings, then Connectors, turn on Developer mode under Advanced, choose Create, paste https://mcp.postfa.st/mcp and approve the OAuth sign-in. A paid ChatGPT plan is required; on Business, Enterprise and Edu workspaces an admin enables custom connectors first. Steps: ChatGPT connector.
• Claude: Customize, then Connectors, Add custom connector, paste the same URL, approve the sign-in. Works on Claude Free (one custom connector), Pro, Max, Team and Enterprise. Steps: Claude connector.
• Claude Code, Cursor, VS Code, Claude Desktop: generate an API key from the API page in the PostFast sidebar and add npx -y postfast-mcp to the client's MCP configuration. Steps and example prompts: Claude Code guide and the MCP server page.

Why we built it this way

We assumed chat users would not want to run a process to talk to a scheduler, so the hosted connector exists for the chat apps, with OAuth so nobody pastes a key into a chat window. We kept the npm package for developers and agent builders who want a local server they can pin, inspect and script. The tool set is not a publishing subset: accounts, posts, media, analytics, follower history and the comment inbox are all there, on every plan. Editing a post after creation and connecting new accounts still happen in the app.

Frequently Asked Questions

When did PostFast launch its MCP server?

The first release, postfast-mcp 0.1.0, was published to npm on March 1, 2026. The hosted OAuth connectors for ChatGPT and Claude followed on June 5, 2026, and the Social Inbox tools arrived with 0.3.0 on August 5, 2026.

Is the MCP server free?

It is included on every PostFast plan, including the 7-day free trial, with no per-seat and no per-conversation charge. PostFast has no free plan; plans start at €12 a month (€10 billed yearly).

Does it work with ChatGPT and Claude?

Yes. Both use the hosted connector at https://mcp.postfa.st/mcp with OAuth sign-in. ChatGPT needs a paid plan with Developer mode; Claude works from the Free plan up, limited to one custom connector on Free.

Can it read comments, not just post?

Yes. Since postfast-mcp 0.3.0 (August 5, 2026) the inbox tools list conversations, reply, hide or delete comments, send Instagram private replies, mark conversations read and assign them to teammates.

Where is the changelog?

Version numbers and dates are on npm under postfast-mcp, release notes are in the project's changelog on GitHub, and the MCP server page documents the tools.

Start with one prompt

Connect the account, then ask for a week of posts. The 7-day free trial covers the API, the MCP server and all 11 platforms from day one.