# MCP Server Access
source: https://docs.chalk.ai/docs/sandboxes/mcp-gateway

## Let sandboxes call your organization's MCP servers through the MCP Gateway without seeing the upstream credentials.

The MCP Gateway lets sandboxes interact with Model Context Protocol servers exposed at your
enterprise — without giving the sandbox direct access to the underlying credentials.

When a sandbox calls the MCP Gateway, it authenticates using its workload identity.
The gateway validates the identity, then proxies the request to the upstream MCP server using
credentials managed by your organization. The sandbox never sees the real credential.

```
┌─────────────┐        WIF token         ┌─────────────┐     real credential     ┌─────────────┐
│   Sandbox   │ ──────────────────────▸  │ MCP Gateway │ ──────────────────────▸ │  MCP Server │
└─────────────┘                          └─────────────┘                         └─────────────┘
```

This is particularly useful for agent workloads. A code-generation agent may need to call
tool-use APIs, search indexes, or retrieval services. With the gateway:

- The agent can leak its own temporary token without compromising the real upstream credential.
- You retain centralized control over which MCP servers are reachable and by which workloads.
- Audit logs capture every proxied call, tied to the originating workload identity.