Plugins become the packaged extension, with a review portal behind them
On 25 September 2026, Anthropic published the product post “Build plugins for Claude.” The same day, ClaudeDevs said plugins are the main way for third-party developers to create extensions for Claude, and that one discovery experience will roll out across Claude and Claude Code over the coming weeks.
The blog says a plugin packages MCP connectors, Agent Skills, or both. An MCP connector is the plugin piece that points at an MCP server you build and host so Claude can reach a product or data. Agent Skills are instruction files that teach Claude a workflow: the steps, defaults, and what good output looks like. The Build for Claude overview says a plugin can also include an MCP App for interactive UI in the conversation, plus commands (named actions) and agents (specialists Claude can delegate to). A plugin with only one of those pieces is still complete. The blog adds that in Claude Code, a plugin can also include LSPs, commands, hooks, and agents.
Once added, the docs say a plugin is meant to run on claude.ai, in the desktop and mobile apps, in Cowork (a Claude product surface alongside chat and Claude Code), and in Claude Code. Chat, Cowork, and Claude Code each load different parts of a plugin, so feature support varies by surface. Developers submit through the portal; each submission is checked and safety-scanned on the way in. Anthropic says you can see review status, scan results, and recommended changes, then choose when to publish after approval. Live listings get usage analytics: installs by product surface and version, listing views, and the searches that lead people to the listing. The overview names a directory-plugin measure page covering installs, versions, how often each skill and MCP server runs, and error rates. It also names measure pages for a directory connector’s server health, Claude Code plugin telemetry across an organization, and how a plugin is used on claude.ai inside an organization, shown in Customize. Those pages name the metrics, with no sample numbers.
The blog says Claude supports the latest MCP spec, commonly referred to as MCP 2.0, which includes a stateless core, plus two extensions: MCP Apps for interactive UI inside chat, and Enterprise Managed Auth for zero-touch OAuth for enterprise users. Support for more MCP features and extensions is described as coming soon. Skills and MCP connectors stay as building blocks, and the Claude directory will continue to list them. Anthropic says developers will later be able to turn a connector listing into a plugin. If you have an existing skill, connector, or plugin on the Claude directory, you do not need to make any changes.
Paid Claude plans can submit and add without a partner application first
The blog states the directory submission portal is open to developers on paid Claude plans. The docs say listings go to Anthropic’s directory at claude.ai/directory, the catalog inside Claude where people find and add plugins and connectors, so that anyone on a paid plan can add an approved plugin. Anthropic checks each submission before it is listed, and there is no partner program to apply to first. These pages do not name plan SKUs or dollar prices. The same blog page lists a related 23 September 2026 title, “Claude Marketplace: one place to discover plugins, agents, and services from our partners.”
There are two publish paths. A single MCP connector points at your remote MCP server. A plugin bundle combines MCP servers and skills, is hosted on GitHub, and is submitted as a repo. The docs also say to submit the MCP server as a connector even when the plugin already references it.
| Item | Kind | Anthropic’s stated rule |
|---|---|---|
| Submit a plugin to the directory | Directory gate | Developers on paid Claude plans |
| Add an approved listing | Directory gate | Anyone on a paid plan, at claude.ai/directory |
| Partner program before submission | Directory gate | None to apply to first |
| Unified discovery | Schedule | Rolls out across Claude and Claude Code over the coming weeks |
| claude plugin eval | Local cost | Each run is a real model call that counts against plan usage or an API bill |
Lay out a plugin, test per surface, then publish through the directory
Anthropic’s overview walks builders through a folder and manifest, SKILL.md files, an optional MCP server and MCP Apps UI, a test on each surface, then a directory listing. Most checking tools live in Claude Code, which the overview describes as Anthropic’s command-line coding tool. The docs say you will want it to build a plugin. The listed commands are claude plugin validate (manifest and component files), claude --plugin-dir (load a local folder), and claude plugin eval, which runs eval cases you write and compares Claude’s results with and without the plugin. The path passed to --plugin-dir is an illustrative argument; the overview documents the flag without printing a path. Each eval run is a real model call that counts against your plan’s usage or your API bill. In a session, /skill-doctor shows what each installed skill costs in context and how often Claude has invoked it. Anthropic also publishes skill-creator, plugin-dev, and mcp-server-dev helpers.
claude plugin validate
claude --plugin-dir /path/to/plugin
claude plugin evalDiscovery is still rolling out, and prices stay off these pages
The unified discovery experience is dated only as “over the coming weeks.” Anthropic does not say which surface gets it first, and these pages do not give a general-availability date. The blog’s review and analytics screenshots are labeled illustrative. These pages do not list free-plan behavior, plan SKU names, or dollar prices for directory submit or add. “Coming soon” MCP features are unnamed. Builders start from the plugin docs and the directory at claude.ai/directory.
Source
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Sources and editorial approach
Read the full ClaudeDevs post of 25 September 2026 against the complete extracted text of Anthropic’s product blog and the Build for Claude overview. Claims are treated as verified only where those official pages state them. The 23 September 2026 Marketplace related-post title is recorded from that blog page’s related list; the Marketplace page itself was not fetched. The Claude Code changelog was not used as a launch note for the directory portal. No product test of the portal, directory, or MCP Apps.