experimental-ext-interceptors/go/sdk/README.md
Ukjae Jeong 2b1d10093e
Import revised sep and update the sep number (#21)
Interceptor SEP has been moved from
https://github.com/modelcontextprotocol/modelcontextprotocol/issues/1763
to
https://github.com/modelcontextprotocol/modelcontextprotocol/issues/2624
.
This PR updates the SEP references over the codebase and import revised
SEP

Signed-off-by: Ukjae Jeong <jeongukjae@gmail.com>
2026-06-16 05:16:21 +01:00

60 lines
1.9 KiB
Markdown

# MCP Interceptors - Go Implementation
Go implementation of the MCP Interceptor Extension based on
[SEP-2624](https://github.com/modelcontextprotocol/modelcontextprotocol/issues/2624).
Note: Currently the MCP SDK is vendored, in-order to add the Protocol Methods needed for interceptors.
## Quick Start
```go
mcpServer := mcp.NewServer(&mcp.Implementation{
Name: "my-server",
Version: "0.1.0",
}, nil)
// Create an extension and register interceptors.
ext := extension.New()
// Register a validator that blocks dangerous tool calls.
ext.AddInterceptor(&interceptors.Validator{
Metadata: interceptors.Metadata{
Name: "block-dangerous",
Hook: interceptors.Hook{
Events: []string{interceptors.EventToolsCall},
Phase: interceptors.PhaseRequest,
},
Mode: interceptors.ModeEnforce,
},
Handler: func(_ context.Context, inv *interceptors.Invocation) (*interceptors.ValidationResult, error) {
raw := inv.Payload.(json.RawMessage)
var params struct{ Name string `json:"name"` }
json.Unmarshal(raw, &params)
// validate the request...
return &interceptors.ValidationResult{Valid: true}, nil
},
})
// Install on the server and create a chain for middleware.
ext.Install(mcpServer)
chain, err := ext.LocalChain(ctx, mcpServer)
mcpServer.AddReceivingMiddleware(gomiddleware.Middleware(chain))
mcpServer.Run(context.Background(), &mcp.StdioTransport{})
```
See [`examples/`](examples/) for complete working examples.
## Documentation
- [**DESIGN.md**](doc/DESIGN.md) — architecture, execution model, integration
with the go-sdk.
- [**PERFORMANCE.md**](doc/PERFORMANCE.md) — per-request cost model, allocation
summary, and optimization notes.
- [**CONFORMANCE.md**](doc/CONFORMANCE.md) — SEP conformance status.
Package API documentation is available via `go doc`:
```sh
go doc github.com/modelcontextprotocol/ext-interceptors/go/sdk/interceptors
```