One, as an Agent Plugin

700+ apps in your agent, packaged to the Agent Plugins 1.0.0 standard. One directory that ChatGPT, Codex, Cursor, GitHub Copilot, Kiro and VS Code all read the same way.

one/
├── plugin.json      # manifest
├── mcp.json         # One's remote MCP server, OAuth, nothing to install
├── .mcp.json        # same server, in the filename GitHub Copilot CLI reads
├── assets/logo.png  # marketplace logo
├── LICENSE          # MIT
└── skills/
    ├── one-integrations/    # how to act in real apps without guessing parameters
    └── integration-code/    # how to write integration code against real schemas

What you get

The MCP server exposes four tools, no matter how many apps you connect:

The two skills are the half that a bare MCP entry does not give you. They teach the agent the search, read, then execute discipline that keeps it from inventing a field name and writing the wrong thing to a real account, and they tell it what to do when a platform is not connected or a call comes back 401.

Related MCP server: Enterprise MCP Gateway and Tool Registry

Install

Cursor. Once listed, install One from the Cursor Marketplace or from Customize in the sidebar. To try it before that, load it locally:

git clone https://github.com/withoneai/one-agent-plugin.git
ln -s "$PWD/one-agent-plugin" ~/.cursor/plugins/local/one

Then restart Cursor (or run Developer: Reload Window), open Customize, and confirm the two skills and the one MCP server appear. The first tool call opens One's OAuth consent screen in your browser.

Kiro. Open the Powers panel, choose Add Custom Power, then Import power from GitHub and paste https://github.com/withoneai/one-agent-plugin (or Import power from a folder for a local clone). Kiro activates the power when you mention an app or task it covers (email, Slack, Stripe, CRM, invoices, and so on) and loads the skills and the one MCP server automatically. First-time sign-in: Kiro does not open the browser on its own for a new remote server. Open the Kiro panel, MCP Servers tab, right-click power-one-agent-plugin-one, choose Reauthenticate, and approve in One's consent screen. (MCP must be enabled in Kiro settings: Configure MCP = Enabled.) Once listed, it will also be one click at kiro.dev/powers.

GitHub Copilot CLI. Once listed in awesome-copilot, install with:

copilot plugin install one@awesome-copilot

Until then, install straight from the repo (or a local clone path):

copilot plugin install withoneai/one-agent-plugin

Copilot reads the server from .mcp.json; copilot mcp list shows it as one. The first tool call opens One's OAuth consent screen. If the server shows needs-auth, run /mcp auth one inside Copilot to trigger the browser flow.

Other clients. Any Agent Plugins client (ChatGPT and Codex, Kiro, VS Code) loads this directory the same way; point it at the repo or a local clone.

Auth

There is no key in this package. The MCP server uses OAuth: the first connect opens a browser, and the consent screen is where you scope the agent to specific connections, read-only, or knowledge-only mode. The Agent Plugins spec forbids secrets in headers and env (§7.2.1, §9.2), which rules out shipping a token here even if we wanted to.

One plugin per platform

platforms/ holds a conformant plugin for every platform in One's catalog, generated from the knowledge base:

platforms/one-quickbooks/
├── plugin.json
├── mcp.json
└── skills/quickbooks/SKILL.md

Each skill carries that platform's real action ids, HTTP methods and paths, so an agent can go straight to reading an action's parameters instead of spending a turn on search, and cannot invent an action that does not exist. The tables are generated, never hand-written.

Regenerate them:

ONE_SECRET=... npm run generate            # every platform
ONE_SECRET=... npm run generate -- --platform shopify

Every generated plugin is validated before it is written; anything that fails is dropped and reported rather than shipped. platforms/index.json lists what was produced.

These plugins are derived from One's knowledge base, so they carry the One-Knowledge-1.0 license and its attribution requirement rather than MIT. The root plugin and the tooling are MIT.

Verify conformance

npm install
npm run validate                    # this plugin
npm run validate platforms/one-*    # every generated plugin

The validator checks plugin.json and mcp.json against the official 1.0.0 JSON Schemas (vendored under schemas/, since the spec forbids fetching a schema at load time), then checks the requirements the schemas cannot express: name constraints (§5.5), plugin root containment (§4.1), HTTPS and no-credentials rules for remote servers (§7.2.1), reserved environment names (§9.2), spec version match between the two files (§10.1), and Agent Skills frontmatter on every skill.

Support and privacy

• Support: support@withone.ai, or the docs at https://www.withone.ai/docs/mcp

• Privacy Policy: https://www.withone.ai/privacy

• Terms: https://www.withone.ai/terms

Links

• One MCP docs: https://www.withone.ai/docs/mcp

• Why four tools: https://www.withone.ai/mcp-efficiency

• Agent Plugins spec: https://github.com/agentplugins/agent-plugins-spec

MIT