Tools for AI Agent Communication Protocols (MCP, ACP, A2A). Inspector, Gateway (planned), Protocol Translation (planned).
AI agents communicate using different protocols, each with their own tools and formats. Say2 provides a single pane of glass to inspect them all.
| Protocol | What It Is | Use Case |
|---|---|---|
| MCP | Model Context Protocol | AI ↔ Tools (Anthropic) |
| ACP | Agent Client Protocol | IDE ↔ Coding Agents (Zed) |
| A2A | Agent-to-Agent | Multi-agent workflows (Google) |
| Version | Focus | Status |
|---|---|---|
| v1 | Multi-protocol Inspection | 🚧 In Progress |
| v2 | Gateway (routing, rate limiting) | 📋 Planned |
| v3 | Protocol Translation (MCP ↔ ACP) | 📋 Planned |
- MCP Inspection - Observe tool calls, resources, prompts
- ACP Inspection - Debug IDE ↔ agent sessions, view agent thoughts
- A2A Inspection - Monitor agent-to-agent task flows
- Unified Dashboard - Single UI for all protocols
- Two Operating Modes
- Built-in client (manual testing)
- Transparent proxy (inspect real traffic)
- Export Traces - Save inspection logs for sharing
| Technology | Choice | Reason |
|---|---|---|
| Runtime | Bun | Fast startup, native TypeScript, modern APIs |
| Language | TypeScript | Type safety, SDK compatibility |
| Web Framework | Hono | Lightweight, Bun-optimized |
| MCP SDK | @modelcontextprotocol/sdk | Official MCP client/server support |
say2/
├── packages/
│ ├── core/ # Shared proxy & transport logic
│ ├── server/ # HTTP proxy server
│ └── web/ # React inspection UI
├── package.json # Workspace root
└── README.md
- Bun v1.0+
# Clone
git clone git@github.com:context-engine/say2.git
cd say2
# Install dependencies
bun install
# Start development
bun run dev# Mode 1: Built-in client (test an MCP server)
say2 inspect mcp --command "node my-server.js"
# Mode 2: Transparent proxy (inspect real traffic)
say2 proxy --port 8080 --target http://mcp-server:3000┌──────────────┐ ┌─────────────────────────────────────┐ ┌──────────────┐
│ Client │────►│ Say2 │────►│ Server │
│ (Claude, IDE)│ │ ┌─────────┐ ┌────────────────┐ │ │ (MCP, ACP, │
│ │◄────│ │ Inspect │ │ Web Dashboard │ │◄────│ A2A Agent) │
└──────────────┘ │ └─────────┘ └────────────────┘ │ └──────────────┘
└─────────────────────────────────────┘
Apache 2.0