# ToolGate Schema MCP server

> Validates MCP tool-call arguments against a JSON Schema to reject malformed requests before they reach the backend.

- Repository: https://github.com/mcpg-dev/mcpg-plugin-tool-gate-schema
- Page: https://hostedmcp.org/servers/mcpg-dev/mcpg-plugin-tool-gate-schema
- Transport: —
- Stars: 0
- License: Apache-2.0

## Tools (7)

- `schema`
- `pointer`
- `max_errors`
- `code`
- `http_status`
- `deny_message`
- `mcpg-plugin-transform-json-schema`

## FAQ

### How does the plugin handle invalid configurations?

The gateway fails to boot rather than running with an unenforced contract if a schema does not compile or contains unknown keys.

### Can the plugin fetch remote JSON Schema references?

No, it only resolves in-document $ref locally and does not fetch remote references to ensure no outbound dependencies.

### How can I prevent leaking schema details in error messages?

You can set the `deny_message` field to a fixed string, which suppresses all schema detail in the response.

### What happens if a JSON Pointer is provided but does not resolve?

If a pointer is used to scope validation and it does not resolve, the call is denied.