MCPO
MCPO is a proxy that converts MCP servers into OpenAPI-compatible HTTP endpoints, allowing standard REST clients and LLM agents expecting OpenAPI interfaces to consume MCP tools without protocol-specific integration.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
MCP server proxy/orchestrator. Aggregates multiple MCP servers — single point of compromise. Auth per upstream server. Audit logging important at proxy layer.
⚡ Reliability
Best When
You want to bridge MCP tools into an existing OpenAPI ecosystem, especially Open WebUI, and need auto-generated /docs without writing any adapter code.
Avoid When
Your agents already support MCP natively, or you need advanced gateway features like rate limiting, RBAC, or observability.
Use Cases
- • Exposing stdio-based MCP tools as standard REST endpoints for Open WebUI or other LLM frontends
- • Making MCP tools accessible to any OpenAPI-compatible agent framework or tool
- • Running multiple MCP servers behind a single HTTP proxy with auto-generated interactive documentation
Not For
- • Native MCP clients that already speak the MCP protocol directly
- • Users who need aggregation logic, RBAC, or multi-tenancy beyond basic API key auth
- • Production deployments requiring high-availability or SLA guarantees
Interface
Authentication
API key via --api-key parameter. OAuth 2.1 with dynamic client registration for secured upstream MCP servers. Custom headers supported for SSE connections.
Pricing
MIT licensed. No cost.
Agent Metadata
Known Gotchas
- ⚠ Translation layer between MCP and OpenAPI may lose some MCP-specific metadata or error context
- ⚠ Hot-reload of config file may cause brief unavailability of tools during reload
- ⚠ OAuth 2.1 dynamic client registration adds complexity for agents expecting simple API key flows
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for MCPO.
Scores are editorial opinions as of 2026-03-06.