Add OpenSumi to client list (#120)

Co-authored-by: David Soria Parra <167242713+dsp-ant@users.noreply.github.com>

clients.mdx

@@ -27,6 +27,7 @@ This page provides an overview of applications that support the Model Context Pr
 | [TheiaAI/TheiaIDE][TheiaAI/TheiaIDE]        | ❌          | ❌        | ✅      | ❌         | ❌    | Supports tools for Agents in Theia AI and the AI-powered Theia IDE          |
 | [Windsurf Editor][Windsurf]                 | ❌          | ❌        | ✅      | ❌         | ❌    | Supports tools with AI Flow for collaborative development.                  |
 | [Zed][Zed]                                  | ❌          | ✅        | ❌      | ❌         | ❌    | Prompts appear as slash commands                                            |
+| [OpenSumi][OpenSumi]                        | ❌          | ❌        | ✅      | ❌         | ❌    | Supports tools in OpenSumi                                                  |
 
 [Claude]: https://claude.ai/download
 [Cursor]: https://cursor.com
@@ -215,6 +216,13 @@ Theia AI and Theia IDE's MCP integration provide users with flexibility, making
 - Tight integration with editor features and workspace context
 - Does not support MCP resources
 
+### OpenSumi
+[OpenSumi](https://github.com/opensumi/core) is a framework helps you quickly build AI Native IDE products.
+
+**Key features:**
+- Supports MCP tools in OpenSumi
+- Supports built-in IDE MCP servers and custom MCP servers
+
 ## Adding MCP support to your application
 
 If you've added MCP support to your application, we encourage you to submit a pull request to add it to this list. MCP integration can provide your users with powerful contextual AI capabilities and make your application part of the growing MCP ecosystem.