Add Stable third-party MCP plugin

.cursor-plugin/marketplace.json

@@ -408,6 +408,11 @@
       "source": "third_party/hunter",
       "description": "Find and verify emails, discover companies, and save leads."
     },
+    {
+      "name": "stable",
+      "source": "third_party/stable",
+      "description": "Find mail, read scanned documents, and call Stable API endpoints."
+    },
     {
       "name": "gamma",
       "source": "third_party/gamma",

README.md

@@ -78,6 +78,7 @@ Official Cursor plugins for popular developer tools, frameworks, and SaaS produc
 | `meta-ads` | [Meta Ads](third_party/meta-ads/) | Cursor | Integrations | Manage campaigns, ads, audiences, and catalogs, and pull performance insights. |
 | `attio` | [Attio](third_party/attio/) | Cursor | Integrations | Search and update CRM records, lists, notes, and tasks. |
 | `hunter` | [Hunter](third_party/hunter/) | Cursor | Integrations | Find and verify emails, discover companies, and save leads. |
+| `stable` | [Stable](third_party/stable/) | Cursor | Integrations | Find mail, read scanned documents, and call Stable API endpoints. |
 | `gamma` | [Gamma](third_party/gamma/) | Cursor | Integrations | Generate presentations, documents, and webpages. |
 | `teams` | [Teams](third_party/teams/) | Cursor | Productivity | Search, read, and send Microsoft Teams chats and channel messages. |
 | `sharepoint` | [SharePoint](third_party/sharepoint/) | Cursor | Productivity | Search and read Microsoft SharePoint sites, document libraries, files, and lists. |

third_party/stable/.cursor-plugin/plugin.json

@@ -0,0 +1,47 @@
+{
+  "name": "stable",
+  "displayName": "Stable",
+  "version": "1.0.0",
+  "minClientVersions": {
+    "cursor": "3.13.0"
+  },
+  "description": "Find mail, read scanned documents, and call Stable API endpoints.",
+  "author": {
+    "name": "Cursor",
+    "email": "plugins@cursor.com"
+  },
+  "homepage": "https://usestable.com",
+  "repository": "https://github.com/cursor/plugins",
+  "license": "MIT",
+  "logo": "assets/logo.png",
+  "keywords": [
+    "stable",
+    "mail",
+    "virtual mailbox",
+    "documents",
+    "scans",
+    "api",
+    "mcp"
+  ],
+  "category": "integrations",
+  "tags": [
+    "stable",
+    "mail",
+    "documents",
+    "mcp"
+  ],
+  "variables": {
+    "type": "object",
+    "properties": {
+      "STABLE_API_KEY": {
+        "type": "string",
+        "title": "Stable API key",
+        "description": "API key from the Stable dashboard (https://dashboard.usestable.com/settings/api-keys)."
+      }
+    },
+    "required": [
+      "STABLE_API_KEY"
+    ]
+  },
+  "mcpServers": "./mcp.json"
+}

third_party/stable/CHANGELOG.md

@@ -0,0 +1,9 @@
+# Changelog
+
+All notable changes to this plugin will be documented here.
+
+## 1.0.0 — initial release
+
+- Added the `stable` MCP server pointing at Stable's hosted Streamable HTTP endpoint (`https://mcp.usestable.com/mcp`).
+- Auth uses a Stable API key supplied by the user as an `x-api-key` header (`${STABLE_API_KEY}`).
+- Logo: Stable's mark from the `useStable` GitHub organization.

third_party/stable/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/stable/README.md

@@ -0,0 +1,69 @@
+# Stable
+
+Cursor plugin that connects agents to [Stable](https://usestable.com) through Stable's hosted [Model Context Protocol](https://modelcontextprotocol.io/) server.
+
+Find mail in a Stable mailbox, read scanned mail documents, and look up or call Stable API endpoints.
+
+## Install
+
+1. Open **Cursor Settings → Plugins**.
+2. Search for **Stable**.
+3. Click **Install**, then set your Stable API key (below).
+
+Or run `/add-plugin stable` in chat.
+
+## MCP
+
+```json
+{
+  "mcpServers": {
+    "stable": {
+      "type": "http",
+      "url": "https://mcp.usestable.com/mcp",
+      "headers": {
+        "x-api-key": "${STABLE_API_KEY}"
+      }
+    }
+  }
+}
+```
+
+Auth is a Stable **API key** sent in an `x-api-key` header. Create one in the Stable dashboard at https://dashboard.usestable.com/settings/api-keys, then set it in **Dashboard → Plugins → Configure**. Do not commit the key.
+
+Stable's official API client documents the same header: "Your Stable API key. Passed as the `x-api-key` header on every request." See https://docs.usestable.com/reference/authentication.
+
+## Before you connect
+
+You need a Stable account and an API key. Tool calls run with the permissions attached to that key.
+
+## What agents can do
+
+| Tool | Capabilities |
+| --- | --- |
+| `find-mail` | Find mail in the Stable mailbox |
+| `read-mail-document` | Read a scanned mail document |
+| `list-endpoints` | List Stable API endpoints available to the key |
+| `get-endpoint` | Get one Stable API endpoint |
+| `search-endpoints` | Search Stable API endpoints |
+| `execute-request` | Run a request against a Stable API endpoint |
+
+The hosted runtime is the source of truth for tool names and schemas.
+
+## Notes
+
+- This plugin sends the API key as `x-api-key` on Streamable HTTP requests to `https://mcp.usestable.com/mcp`. That is the header Stable's public API client documents for `https://api.usestable.com`.
+- Do not commit `STABLE_API_KEY`.
+
+## Docs
+
+- Stable: https://usestable.com
+- API reference: https://docs.usestable.com
+- Authentication: https://docs.usestable.com/reference/authentication
+- API keys: https://dashboard.usestable.com/settings/api-keys
+- Server URL: https://mcp.usestable.com/mcp
+
+Logo is Stable's mark from the `useStable` GitHub organization. The usestable.com site was not reachable when this plugin was added, so the file was not downloaded from the website.
+
+## License
+
+MIT

third_party/stable/mcp.json

@@ -0,0 +1,11 @@
+{
+  "mcpServers": {
+    "stable": {
+      "type": "http",
+      "url": "https://mcp.usestable.com/mcp",
+      "headers": {
+        "x-api-key": "${STABLE_API_KEY}"
+      }
+    }
+  }
+}