feat(third_party): add Square plugin

.cursor-plugin/marketplace.json

@@ -522,6 +522,11 @@
       "name": "workday",
       "source": "third_party/workday",
       "description": "Look up workers, organizations, time off, payroll, and recruiting data in Workday."
+    },
+    {
+      "name": "square",
+      "source": "third_party/square",
+      "description": "Work with payments, orders, catalog, customers, and invoices."
     }
   ]
 }

README.md

@@ -96,6 +96,7 @@ Official Cursor plugins for popular developer tools, frameworks, and SaaS produc
 | `shopify-store` | [Shopify](third_party/shopify-store/) | Cursor | Integrations | Connect your Shopify store so Grok can answer questions about products, orders, customers, inventory, and sales. |
 | `quickbooks-online` | [QuickBooks Online](third_party/quickbooks-online/) | Cursor | Integrations | Read invoices, bills, expenses, customers, accounts, and financial reports. |
 | `workday` | [Workday](third_party/workday/) | Cursor | Integrations | Look up workers, organizations, time off, payroll, and recruiting data in Workday. |
+| `square` | [Square](third_party/square/) | Cursor | Integrations | Work with payments, orders, catalog, customers, and invoices. |
 Author values match each plugin’s `plugin.json` `author.name` (Cursor lists `plugins@cursor.com` in the manifest).
 
 ## Repository structure

third_party/square/.cursor-plugin/plugin.json

@@ -0,0 +1,38 @@
+{
+  "name": "square",
+  "displayName": "Square",
+  "version": "1.0.0",
+  "minClientVersions": {
+    "cursor": "3.13.0"
+  },
+  "description": "Work with payments, orders, catalog, customers, and invoices.",
+  "author": {
+    "name": "Cursor",
+    "email": "plugins@cursor.com"
+  },
+  "homepage": "https://developer.squareup.com/docs/mcp",
+  "repository": "https://github.com/cursor/plugins",
+  "license": "MIT",
+  "logo": "assets/logo.png",
+  "keywords": [
+    "square",
+    "payments",
+    "point of sale",
+    "pos",
+    "orders",
+    "catalog",
+    "inventory",
+    "customers",
+    "invoices",
+    "commerce",
+    "mcp"
+  ],
+  "category": "integrations",
+  "tags": [
+    "square",
+    "payments",
+    "commerce",
+    "mcp"
+  ],
+  "mcpServers": "./mcp.json"
+}

third_party/square/CHANGELOG.md

@@ -0,0 +1,9 @@
+# Changelog
+
+All notable changes to this plugin will be documented here.
+
+## 1.0.0 — initial release
+
+- Added the `square` MCP server pointing at `https://mcp.squareup.com/mcp`.
+- Auth uses OAuth — no access token or client ID to configure.
+- Logo: Square's official mark, from the `square` GitHub organization.

third_party/square/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Cursor
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

third_party/square/README.md

@@ -0,0 +1,62 @@
+# Square
+
+Cursor plugin that connects agents to [Square](https://squareup.com) through Square's official remote [Model Context Protocol](https://modelcontextprotocol.io/) server, hosted by Block.
+
+Query and manage a Square seller account — payments, orders, catalog items, inventory, customers, invoices, and more — through the Square API.
+
+## Install
+
+1. Open **Cursor Settings → Plugins**.
+2. Search for **Square**.
+3. Click **Install**, then complete the Square sign-in prompt.
+
+Or run `/add-plugin square` in chat.
+
+## MCP
+
+```json
+{
+  "mcpServers": {
+    "square": {
+      "type": "http",
+      "url": "https://mcp.squareup.com/mcp"
+    }
+  }
+}
+```
+
+Auth is OAuth 2.1 with Dynamic Client Registration and PKCE. Cursor registers itself and prompts for Square sign-in when the plugin connects — there is no access token or client ID to configure. Square lets you approve only the permission scopes you want the connection to have.
+
+## What agents can do
+
+The server exposes a small, generic tool set that reaches the full Square API:
+
+| Tool | Purpose |
+| --- | --- |
+| `get_service_info` | Discover the methods available on a Square service (for example `catalog`, `orders`, `payments`) |
+| `get_type_info` | Get the parameter requirements for a method before calling it |
+| `make_api_request` | Execute a Square API call |
+
+Through those tools agents can reach payments and refunds, orders, catalog and inventory, customers and loyalty, invoices and subscriptions, bookings, team members and timecards, gift cards, disputes, payouts, and more — limited to the scopes you approve.
+
+The hosted runtime is the source of truth for tool names and schemas.
+
+## Notes
+
+- The remote server reaches **production** data only. To test against a Square Sandbox account, run Square's local server instead (`npx square-mcp-server start` with `ACCESS_TOKEN` and `SANDBOX=true`); see Square's docs.
+- The server can write as well as read — including creating orders, payments, refunds, and invoices — when the matching `*_WRITE` scopes are approved. Approve only the scopes you need, and grant read-only scopes if agents should not change seller data.
+- Square labels the MCP server as beta.
+- Square maintains an allowlist of MCP clients for OAuth registration. If sign-in is rejected for an unregistered client, request an addition in the Square developer forum.
+
+## Docs
+
+- Square MCP server: https://developer.squareup.com/docs/mcp
+- Source: https://github.com/square/square-mcp-server
+- OAuth permissions reference: https://developer.squareup.com/docs/oauth-api/square-permissions
+- Server URL: https://mcp.squareup.com/mcp
+
+Logo is Square's official mark, from the `square` GitHub organization.
+
+## License
+
+MIT

third_party/square/mcp.json

@@ -0,0 +1,8 @@
+{
+  "mcpServers": {
+    "square": {
+      "type": "http",
+      "url": "https://mcp.squareup.com/mcp"
+    }
+  }
+}