MCP Zero-Trust Proxy vs MCP Auth Proxy (sigbit) -- 2026 Comparison

Quick Verdict

Choose sigbit if you only need OAuth authentication and have no compliance or multi-user requirements — it’s free and does that job well. Choose MCP Zero-Trust Proxy if you need tool-level RBAC, session isolation, audit logging, rate limiting, or multi-tenant deployments.

Feature Comparison

Feature	MCP Zero-Trust Proxy	MCP Auth Proxy (sigbit)
OAuth Authentication	✓ GitHub, Google, OIDC	✓ OAuth 2.0
OAuth 2.1 PKCE	✓ Full PKCE flow	✗ OAuth 2.0 only
Tool-Level RBAC	✓ Per-tool, per-user rules	✗ Not available
Session Isolation	✓ Per-user session store	✗ Not available
Audit Logging	✓ JSONL, file rotation	✗ Not available
Rate Limiting	✓ Per-client token bucket	✗ Not available
Multi-Provider Auth	✓ GitHub, Google, OIDC	Varies
Docker Deployment	✓ Single-command	✓ Available
Drop-in Proxy	✓ Zero server changes	✓ Zero server changes
Pricing	Free (1 server) — $49/mo Pro — $199/mo Enterprise	Free, open-source (MIT)
License	Commercial (Free tier available)	MIT (fully open-source)

When to Choose Each

Choose MCP Auth Proxy (sigbit) if…

You only need OAuth authentication — no RBAC or audit trail required
You have a single developer or a fully trusted team with no access differentiation
Budget is zero — it’s free and open-source with no limits
You have no compliance requirements (SOC 2, audit, regulatory)
You want to inspect and modify the source code yourself
Your threat model is “keep unauthenticated users out” and nothing more

Choose MCP Zero-Trust Proxy if…

You need different users to have different tool permissions (RBAC)
You need an audit trail of every tool call for compliance or debugging
You’re running a multi-tenant setup (one proxy, multiple clients)
You need rate limiting to protect your MCP servers from abuse
You need session isolation so users can’t affect each other’s state
You’re building a production system that requires enterprise-grade security

About MCP Auth Proxy (sigbit)

MCP Auth Proxy by theailanguage (known as sigbit in the community) is a solid, straightforward open-source project that does exactly what it promises: adds OAuth authentication to MCP servers with zero server modifications. It’s a well-designed tool for developers who only need authentication and have no compliance or access-control requirements. It’s genuinely the right choice if your use case is simple — free, no lock-in, and you can read every line of the code.

The gap becomes relevant when teams grow past a single developer, when different users need different permissions, or when any form of auditing or compliance is required. Those capabilities require additional complexity that sigbit intentionally doesn’t include in order to stay simple and focused.

Get Started with MCP Zero-Trust Proxy

One Docker command. Full auth, RBAC, audit logging, and rate limiting. Free tier available — no credit card required.

Get Started Free