---
title: "Security"
description: "Gessa MCP supports OAuth 2.1 with PKCE S256, Resource Indicators, Protected Resource Metadata, Authorization Server Metadata, short-lived access tokens, refresh-token rotation, and scoped MCP API keys for stdio clients."
engineVersion: v1.0.234
date: 2026-09-28
license: "(c) Gessa, proprietary. Cite with attribution to https://gessa.ai/docs/. Terms: https://gessa.ai/terms/."
canonical: https://gessa.ai/docs/creator/mcp/security/
---
# Security

Gessa MCP supports OAuth 2.1 with PKCE S256, Resource Indicators, Protected Resource Metadata, Authorization Server Metadata, short-lived access tokens, refresh-token rotation, and scoped MCP API keys for stdio clients.

Scopes:

- `mcp:read`: read-only tools.
- `mcp:write`: mutating creator tools.
- `mcp:admin`: destructive and live-ops tools.
- `mcp:platform`: platform staff operations.

MCP client bearer tokens are never forwarded to downstream APIs. The resource server validates the credential and derives an internal principal for canonical service calls.