Architecture Reference

Visual Request Pipeline

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Ingress ASCII Flow

Client (Cursor / OpenCode / Claude / Spark)
       │
       ▼
┌─────────────────────────────────────────────────────────────┐
│                 McpMultiplexerHandler                       │
│  ┌─────────────────────────────┐  ┌──────────────────────┐  │
│  │    Streamable HTTP          │  │     Legacy SSE       │  │
│  │   (Stateless POSTs)         │  │   (GET Streams)      │  │
│  └──────────────┬──────────────┘  └──────────┬───────────┘  │
└─────────────────┼────────────────────────────┼──────────────┘
                  ▼                            ▼
┌─────────────────────────────────────────────────────────────┐
│              Stateless OAuth Ingress Middleware             │
│        (Local HMAC-SHA256 JWT Signature & Scopes Gate)      │
└──────────────────────────────┬──────────────────────────────┘
                               ▼
┌─────────────────────────────────────────────────────────────┐
│                Registered MCP Tool Handlers                 │
│         (echo, dictionary_lookup, system_info)              │
└─────────────────────────────────────────────────────────────┘

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Transport Comparison

Feature	Streamable HTTP (Stateless: true)	Legacy SSE (SSEHandler)
Request Model	Independent HTTP POSTs	Persistent GET stream + HTTP POSTs
Session State	None (Self-contained)	In-memory session mapping
Cold-Start Resilience	100% resilient	Requires session affinity
Target Clients	OpenCode, Cursor, Spark, agy	Claude Desktop, legacy SSE clients