move to generated mcp for econet

AGENTS.md

@@ -24,8 +24,14 @@ Exporter for Rheem EcoNet / Rheemcloud water heaters, built on the
   **No MQTT**, so `WiFiSignal` and `Running`/`RunningState` stay zero.
 - `pkg/econet/econetgrpc/` — `EconetService` gRPC impl (`ListDevices`,
   `GetDevice`) + `deviceToProto`. Does **not** own a client; it's injected.
-- `pkg/econet/econetmcp/` — MCP server at `/api/mcp`; the `list_water_heaters`
-  tool delegates to the gRPC server.
+- `pkg/econet/econetmcpgen/` — **active** MCP server at `/api/mcp`. Registers
+  the tools generated by protoc-gen-go-mcp (`api/econet/v1alpha1/v1alpha1mcp/`)
+  against our go-sdk `*mcp.Server` via the `runtime/gosdk` adapter, forwarding
+  in-process to the gRPC server. Exposes the same package API as `econetmcp`.
+- `pkg/econet/econetmcp/` — the older hand-written MCP server; a single
+  `list_water_heaters` tool delegating to the gRPC server. Kept in place as a
+  fallback. **Switch between the two** with the aliased `econetmcp` import in
+  `pkg/econet/econet.go` (one line — both packages export identical symbols).
 - `pkg/econet/econetmetrics/` — OTEL observable gauges (read the client
   snapshot at scrape time; no poller of its own).
 
@@ -68,6 +74,8 @@ that's all it takes — no extra wiring.
 ## Workflow
 
 - Regenerate proto: `make proto` (buf; `PROTO_DIRS=proto/econet/v1alpha1/*`).
+  This also runs the `protoc-gen-go-mcp` plugin (see `buf.gen.yaml`), emitting
+  the MCP registrars under `api/econet/v1alpha1/v1alpha1mcp/`.
 - Regenerate config schema after config changes: `make schema`.
 - Build/test: `go build ./... && go test ./...`.
 - `econetclient.Device` is a plain struct, so `deviceToProto` and the datapoint

api/econet/v1alpha1/v1alpha1mcp/econet.pb.mcp.go

@@ -0,0 +1,316 @@
+// Code generated by protoc-gen-mcp-go. DO NOT EDIT.
+// source: econet/v1alpha1/econet.proto
+
+package v1alpha1mcp
+
+import (
+	v1alpha1 "gitea.libretechconsulting.com/rmcguire/econet-exporter/api/econet/v1alpha1"
+)
+
+import (
+	"context"
+	"encoding/json"
+	"google.golang.org/protobuf/encoding/protojson"
+	"connectrpc.com/connect"
+	grpc "google.golang.org/grpc"
+	"github.com/redpanda-data/protoc-gen-go-mcp/pkg/runtime"
+)
+
+var (
+	EconetService_GetDeviceTool   = runtime.Tool{Name: "econet_v1alpha1_EconetService_GetDevice", Description: "", RawInputSchema: json.RawMessage{0x7b, 0x22, 0x70, 0x72, 0x6f, 0x70, 0x65, 0x72, 0x74, 0x69, 0x65, 0x73, 0x22, 0x3a, 0x7b, 0x22, 0x73, 0x65, 0x72, 0x69, 0x61, 0x6c, 0x5f, 0x6e, 0x75, 0x6d, 0x62, 0x65, 0x72, 0x22, 0x3a, 0x7b, 0x22, 0x6d, 0x69, 0x6e, 0x4c, 0x65, 0x6e, 0x67, 0x74, 0x68, 0x22, 0x3a, 0x31, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x7d, 0x2c, 0x22, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x22, 0x3a, 0x5b, 0x5d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x6f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x22, 0x7d}, RawOutputSchema: json.RawMessage{0x7b, 0x22, 0x70, 0x72, 0x6f, 0x70, 0x65, 0x72, 0x74, 0x69, 0x65, 0x73, 0x22, 0x3a, 0x7b, 0x22, 0x64, 0x65, 0x76, 0x69, 0x63, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x70, 0x72, 0x6f, 0x70, 0x65, 0x72, 0x74, 0x69, 0x65, 0x73, 0x22, 0x3a, 0x7b, 0x22, 0x61, 0x6c, 0x65, 0x72, 0x74, 0x5f, 0x63, 0x6f, 0x75, 0x6e, 0x74, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x61, 0x77, 0x61, 0x79, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x62, 0x6f, 0x6f, 0x6c, 0x65, 0x61, 0x6e, 0x22, 0x7d, 0x2c, 0x22, 0x63, 0x6f, 0x6e, 0x6e, 0x65, 0x63, 0x74, 0x65, 0x64, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x62, 0x6f, 0x6f, 0x6c, 0x65, 0x61, 0x6e, 0x22, 0x7d, 0x2c, 0x22, 0x64, 0x65, 0x76, 0x69, 0x63, 0x65, 0x5f, 0x69, 0x64, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x65, 0x6e, 0x61, 0x62, 0x6c, 0x65, 0x64, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x62, 0x6f, 0x6f, 0x6c, 0x65, 0x61, 0x6e, 0x22, 0x7d, 0x2c, 0x22, 0x66, 0x72, 0x69, 0x65, 0x6e, 0x64, 0x6c, 0x79, 0x5f, 0x6e, 0x61, 0x6d, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x67, 0x65, 0x6e, 0x65, 0x72, 0x69, 0x63, 0x5f, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x68, 0x6f, 0x74, 0x5f, 0x77, 0x61, 0x74, 0x65, 0x72, 0x5f, 0x61, 0x76, 0x61, 0x69, 0x6c, 0x61, 0x62, 0x69, 0x6c, 0x69, 0x74, 0x79, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x6c, 0x61, 0x73, 0x74, 0x5f, 0x75, 0x70, 0x64, 0x61, 0x74, 0x65, 0x64, 0x22, 0x3a, 0x7b, 0x22, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x22, 0x3a, 0x22, 0x64, 0x61, 0x74, 0x65, 0x2d, 0x74, 0x69, 0x6d, 0x65, 0x22, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x5b, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x2c, 0x22, 0x6e, 0x75, 0x6c, 0x6c, 0x22, 0x5d, 0x7d, 0x2c, 0x22, 0x6d, 0x6f, 0x64, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x72, 0x75, 0x6e, 0x6e, 0x69, 0x6e, 0x67, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x62, 0x6f, 0x6f, 0x6c, 0x65, 0x61, 0x6e, 0x22, 0x7d, 0x2c, 0x22, 0x72, 0x75, 0x6e, 0x6e, 0x69, 0x6e, 0x67, 0x5f, 0x73, 0x74, 0x61, 0x74, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x73, 0x65, 0x72, 0x69, 0x61, 0x6c, 0x5f, 0x6e, 0x75, 0x6d, 0x62, 0x65, 0x72, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x73, 0x65, 0x74, 0x70, 0x6f, 0x69, 0x6e, 0x74, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x73, 0x65, 0x74, 0x70, 0x6f, 0x69, 0x6e, 0x74, 0x5f, 0x6d, 0x61, 0x78, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x73, 0x65, 0x74, 0x70, 0x6f, 0x69, 0x6e, 0x74, 0x5f, 0x6d, 0x69, 0x6e, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x77, 0x69, 0x66, 0x69, 0x5f, 0x73, 0x69, 0x67, 0x6e, 0x61, 0x6c, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x7d, 0x2c, 0x22, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x22, 0x3a, 0x5b, 0x5d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x6f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x22, 0x7d, 0x7d, 0x2c, 0x22, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x22, 0x3a, 0x5b, 0x5d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x6f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x22, 0x7d}}
+	EconetService_ListDevicesTool = runtime.Tool{Name: "econet_v1alpha1_EconetService_ListDevices", Description: "", RawInputSchema: json.RawMessage{0x7b, 0x22, 0x70, 0x72, 0x6f, 0x70, 0x65, 0x72, 0x74, 0x69, 0x65, 0x73, 0x22, 0x3a, 0x7b, 0x7d, 0x2c, 0x22, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x22, 0x3a, 0x5b, 0x5d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x6f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x22, 0x7d}, RawOutputSchema: json.RawMessage{0x7b, 0x22, 0x70, 0x72, 0x6f, 0x70, 0x65, 0x72, 0x74, 0x69, 0x65, 0x73, 0x22, 0x3a, 0x7b, 0x22, 0x64, 0x65, 0x76, 0x69, 0x63, 0x65, 0x73, 0x22, 0x3a, 0x7b, 0x22, 0x69, 0x74, 0x65, 0x6d, 0x73, 0x22, 0x3a, 0x7b, 0x22, 0x70, 0x72, 0x6f, 0x70, 0x65, 0x72, 0x74, 0x69, 0x65, 0x73, 0x22, 0x3a, 0x7b, 0x22, 0x61, 0x6c, 0x65, 0x72, 0x74, 0x5f, 0x63, 0x6f, 0x75, 0x6e, 0x74, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x61, 0x77, 0x61, 0x79, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x62, 0x6f, 0x6f, 0x6c, 0x65, 0x61, 0x6e, 0x22, 0x7d, 0x2c, 0x22, 0x63, 0x6f, 0x6e, 0x6e, 0x65, 0x63, 0x74, 0x65, 0x64, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x62, 0x6f, 0x6f, 0x6c, 0x65, 0x61, 0x6e, 0x22, 0x7d, 0x2c, 0x22, 0x64, 0x65, 0x76, 0x69, 0x63, 0x65, 0x5f, 0x69, 0x64, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x65, 0x6e, 0x61, 0x62, 0x6c, 0x65, 0x64, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x62, 0x6f, 0x6f, 0x6c, 0x65, 0x61, 0x6e, 0x22, 0x7d, 0x2c, 0x22, 0x66, 0x72, 0x69, 0x65, 0x6e, 0x64, 0x6c, 0x79, 0x5f, 0x6e, 0x61, 0x6d, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x67, 0x65, 0x6e, 0x65, 0x72, 0x69, 0x63, 0x5f, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x68, 0x6f, 0x74, 0x5f, 0x77, 0x61, 0x74, 0x65, 0x72, 0x5f, 0x61, 0x76, 0x61, 0x69, 0x6c, 0x61, 0x62, 0x69, 0x6c, 0x69, 0x74, 0x79, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x6c, 0x61, 0x73, 0x74, 0x5f, 0x75, 0x70, 0x64, 0x61, 0x74, 0x65, 0x64, 0x22, 0x3a, 0x7b, 0x22, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x22, 0x3a, 0x22, 0x64, 0x61, 0x74, 0x65, 0x2d, 0x74, 0x69, 0x6d, 0x65, 0x22, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x5b, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x2c, 0x22, 0x6e, 0x75, 0x6c, 0x6c, 0x22, 0x5d, 0x7d, 0x2c, 0x22, 0x6d, 0x6f, 0x64, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x72, 0x75, 0x6e, 0x6e, 0x69, 0x6e, 0x67, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x62, 0x6f, 0x6f, 0x6c, 0x65, 0x61, 0x6e, 0x22, 0x7d, 0x2c, 0x22, 0x72, 0x75, 0x6e, 0x6e, 0x69, 0x6e, 0x67, 0x5f, 0x73, 0x74, 0x61, 0x74, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x73, 0x65, 0x72, 0x69, 0x61, 0x6c, 0x5f, 0x6e, 0x75, 0x6d, 0x62, 0x65, 0x72, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x73, 0x65, 0x74, 0x70, 0x6f, 0x69, 0x6e, 0x74, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x73, 0x65, 0x74, 0x70, 0x6f, 0x69, 0x6e, 0x74, 0x5f, 0x6d, 0x61, 0x78, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x73, 0x65, 0x74, 0x70, 0x6f, 0x69, 0x6e, 0x74, 0x5f, 0x6d, 0x69, 0x6e, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x22, 0x7d, 0x2c, 0x22, 0x77, 0x69, 0x66, 0x69, 0x5f, 0x73, 0x69, 0x67, 0x6e, 0x61, 0x6c, 0x22, 0x3a, 0x7b, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x69, 0x6e, 0x74, 0x65, 0x67, 0x65, 0x72, 0x22, 0x7d, 0x7d, 0x2c, 0x22, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x22, 0x3a, 0x5b, 0x5d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x6f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x22, 0x7d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x61, 0x72, 0x72, 0x61, 0x79, 0x22, 0x7d, 0x7d, 0x2c, 0x22, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x22, 0x3a, 0x5b, 0x5d, 0x2c, 0x22, 0x74, 0x79, 0x70, 0x65, 0x22, 0x3a, 0x22, 0x6f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x22, 0x7d}}
+)
+
+// EconetServiceServer is compatible with the grpc-go server interface.
+type EconetServiceServer interface {
+	GetDevice(ctx context.Context, req *v1alpha1.GetDeviceRequest) (*v1alpha1.GetDeviceResponse, error)
+	ListDevices(ctx context.Context, req *v1alpha1.ListDevicesRequest) (*v1alpha1.ListDevicesResponse, error)
+}
+
+// RegisterEconetServiceHandler registers standard MCP handlers for EconetService
+func RegisterEconetServiceHandler(s runtime.MCPServer, srv EconetServiceServer, opts ...runtime.Option) {
+	config := runtime.NewConfig()
+	for _, opt := range opts {
+		opt(config)
+	}
+	GetDeviceTool := EconetService_GetDeviceTool
+	GetDeviceTool = runtime.ApplyConfig(GetDeviceTool, config)
+
+	if config.ShouldRegister(GetDeviceTool.Name) {
+		s.AddTool(GetDeviceTool, func(ctx context.Context, request *runtime.CallToolRequest) (*runtime.CallToolResult, error) {
+			var req v1alpha1.GetDeviceRequest
+
+			message := request.Arguments
+
+			// Extract extra properties if configured
+			for _, prop := range config.ExtraProperties {
+				if propVal, ok := message[prop.Name]; ok {
+					ctx = context.WithValue(ctx, prop.ContextKey, propVal)
+				}
+			}
+
+			// Rewrite oneof discriminated wrappers and recursion placeholders into the
+			// protojson-native shape. Errors are model-readable for self-correction.
+			if err := runtime.DecodeArguments(req.ProtoReflect().Descriptor(), message); err != nil {
+				return runtime.NewToolResultError(err.Error()), nil
+			}
+
+			marshaled, err := json.Marshal(message)
+			if err != nil {
+				return nil, err
+			}
+
+			if err := (protojson.UnmarshalOptions{DiscardUnknown: true}).Unmarshal(marshaled, &req); err != nil {
+				return nil, err
+			}
+
+			resp, err := srv.GetDevice(ctx, &req)
+			if err != nil {
+				return runtime.HandleError(err)
+			}
+
+			structured, err := runtime.EncodeMessage(resp)
+			if err != nil {
+				return nil, err
+			}
+
+			return runtime.NewToolResultJSON(structured), nil
+		})
+	}
+	ListDevicesTool := EconetService_ListDevicesTool
+	ListDevicesTool = runtime.ApplyConfig(ListDevicesTool, config)
+
+	if config.ShouldRegister(ListDevicesTool.Name) {
+		s.AddTool(ListDevicesTool, func(ctx context.Context, request *runtime.CallToolRequest) (*runtime.CallToolResult, error) {
+			var req v1alpha1.ListDevicesRequest
+
+			message := request.Arguments
+
+			// Extract extra properties if configured
+			for _, prop := range config.ExtraProperties {
+				if propVal, ok := message[prop.Name]; ok {
+					ctx = context.WithValue(ctx, prop.ContextKey, propVal)
+				}
+			}
+
+			// Rewrite oneof discriminated wrappers and recursion placeholders into the
+			// protojson-native shape. Errors are model-readable for self-correction.
+			if err := runtime.DecodeArguments(req.ProtoReflect().Descriptor(), message); err != nil {
+				return runtime.NewToolResultError(err.Error()), nil
+			}
+
+			marshaled, err := json.Marshal(message)
+			if err != nil {
+				return nil, err
+			}
+
+			if err := (protojson.UnmarshalOptions{DiscardUnknown: true}).Unmarshal(marshaled, &req); err != nil {
+				return nil, err
+			}
+
+			resp, err := srv.ListDevices(ctx, &req)
+			if err != nil {
+				return runtime.HandleError(err)
+			}
+
+			structured, err := runtime.EncodeMessage(resp)
+			if err != nil {
+				return nil, err
+			}
+
+			return runtime.NewToolResultJSON(structured), nil
+		})
+	}
+}
+
+// EconetServiceClient is compatible with the grpc-go client interface.
+type EconetServiceClient interface {
+	GetDevice(ctx context.Context, req *v1alpha1.GetDeviceRequest, opts ...grpc.CallOption) (*v1alpha1.GetDeviceResponse, error)
+	ListDevices(ctx context.Context, req *v1alpha1.ListDevicesRequest, opts ...grpc.CallOption) (*v1alpha1.ListDevicesResponse, error)
+}
+
+// ConnectEconetServiceClient is compatible with the connectrpc-go client interface.
+type ConnectEconetServiceClient interface {
+	GetDevice(ctx context.Context, req *connect.Request[v1alpha1.GetDeviceRequest]) (*connect.Response[v1alpha1.GetDeviceResponse], error)
+	ListDevices(ctx context.Context, req *connect.Request[v1alpha1.ListDevicesRequest]) (*connect.Response[v1alpha1.ListDevicesResponse], error)
+}
+
+// ForwardToConnectEconetServiceClient registers a connectrpc client, to forward MCP calls to it.
+func ForwardToConnectEconetServiceClient(s runtime.MCPServer, client ConnectEconetServiceClient, opts ...runtime.Option) {
+	config := runtime.NewConfig()
+	for _, opt := range opts {
+		opt(config)
+	}
+	GetDeviceTool := EconetService_GetDeviceTool
+	GetDeviceTool = runtime.ApplyConfig(GetDeviceTool, config)
+
+	if config.ShouldRegister(GetDeviceTool.Name) {
+		s.AddTool(GetDeviceTool, func(ctx context.Context, request *runtime.CallToolRequest) (*runtime.CallToolResult, error) {
+			var req v1alpha1.GetDeviceRequest
+
+			message := request.Arguments
+
+			// Extract extra properties if configured
+			for _, prop := range config.ExtraProperties {
+				if propVal, ok := message[prop.Name]; ok {
+					ctx = context.WithValue(ctx, prop.ContextKey, propVal)
+				}
+			}
+
+			if err := runtime.DecodeArguments(req.ProtoReflect().Descriptor(), message); err != nil {
+				return runtime.NewToolResultError(err.Error()), nil
+			}
+
+			marshaled, err := json.Marshal(message)
+			if err != nil {
+				return nil, err
+			}
+
+			if err := (protojson.UnmarshalOptions{DiscardUnknown: true}).Unmarshal(marshaled, &req); err != nil {
+				return nil, err
+			}
+
+			resp, err := client.GetDevice(ctx, connect.NewRequest(&req))
+			if err != nil {
+				return runtime.HandleError(err)
+			}
+
+			structured, err := runtime.EncodeMessage(resp.Msg)
+			if err != nil {
+				return nil, err
+			}
+			return runtime.NewToolResultJSON(structured), nil
+		})
+	}
+	ListDevicesTool := EconetService_ListDevicesTool
+	ListDevicesTool = runtime.ApplyConfig(ListDevicesTool, config)
+
+	if config.ShouldRegister(ListDevicesTool.Name) {
+		s.AddTool(ListDevicesTool, func(ctx context.Context, request *runtime.CallToolRequest) (*runtime.CallToolResult, error) {
+			var req v1alpha1.ListDevicesRequest
+
+			message := request.Arguments
+
+			// Extract extra properties if configured
+			for _, prop := range config.ExtraProperties {
+				if propVal, ok := message[prop.Name]; ok {
+					ctx = context.WithValue(ctx, prop.ContextKey, propVal)
+				}
+			}
+
+			if err := runtime.DecodeArguments(req.ProtoReflect().Descriptor(), message); err != nil {
+				return runtime.NewToolResultError(err.Error()), nil
+			}
+
+			marshaled, err := json.Marshal(message)
+			if err != nil {
+				return nil, err
+			}
+
+			if err := (protojson.UnmarshalOptions{DiscardUnknown: true}).Unmarshal(marshaled, &req); err != nil {
+				return nil, err
+			}
+
+			resp, err := client.ListDevices(ctx, connect.NewRequest(&req))
+			if err != nil {
+				return runtime.HandleError(err)
+			}
+
+			structured, err := runtime.EncodeMessage(resp.Msg)
+			if err != nil {
+				return nil, err
+			}
+			return runtime.NewToolResultJSON(structured), nil
+		})
+	}
+}
+
+// ForwardToEconetServiceClient registers a gRPC client, to forward MCP calls to it.
+func ForwardToEconetServiceClient(s runtime.MCPServer, client EconetServiceClient, opts ...runtime.Option) {
+	config := runtime.NewConfig()
+	for _, opt := range opts {
+		opt(config)
+	}
+	GetDeviceTool := EconetService_GetDeviceTool
+	GetDeviceTool = runtime.ApplyConfig(GetDeviceTool, config)
+
+	if config.ShouldRegister(GetDeviceTool.Name) {
+		s.AddTool(GetDeviceTool, func(ctx context.Context, request *runtime.CallToolRequest) (*runtime.CallToolResult, error) {
+			var req v1alpha1.GetDeviceRequest
+
+			message := request.Arguments
+
+			// Extract extra properties if configured
+			for _, prop := range config.ExtraProperties {
+				if propVal, ok := message[prop.Name]; ok {
+					ctx = context.WithValue(ctx, prop.ContextKey, propVal)
+				}
+			}
+
+			if err := runtime.DecodeArguments(req.ProtoReflect().Descriptor(), message); err != nil {
+				return runtime.NewToolResultError(err.Error()), nil
+			}
+
+			marshaled, err := json.Marshal(message)
+			if err != nil {
+				return nil, err
+			}
+
+			if err := (protojson.UnmarshalOptions{DiscardUnknown: true}).Unmarshal(marshaled, &req); err != nil {
+				return nil, err
+			}
+
+			resp, err := client.GetDevice(ctx, &req)
+			if err != nil {
+				return runtime.HandleError(err)
+			}
+
+			structured, err := runtime.EncodeMessage(resp)
+			if err != nil {
+				return nil, err
+			}
+			return runtime.NewToolResultJSON(structured), nil
+		})
+	}
+	ListDevicesTool := EconetService_ListDevicesTool
+	ListDevicesTool = runtime.ApplyConfig(ListDevicesTool, config)
+
+	if config.ShouldRegister(ListDevicesTool.Name) {
+		s.AddTool(ListDevicesTool, func(ctx context.Context, request *runtime.CallToolRequest) (*runtime.CallToolResult, error) {
+			var req v1alpha1.ListDevicesRequest
+
+			message := request.Arguments
+
+			// Extract extra properties if configured
+			for _, prop := range config.ExtraProperties {
+				if propVal, ok := message[prop.Name]; ok {
+					ctx = context.WithValue(ctx, prop.ContextKey, propVal)
+				}
+			}
+
+			if err := runtime.DecodeArguments(req.ProtoReflect().Descriptor(), message); err != nil {
+				return runtime.NewToolResultError(err.Error()), nil
+			}
+
+			marshaled, err := json.Marshal(message)
+			if err != nil {
+				return nil, err
+			}
+
+			if err := (protojson.UnmarshalOptions{DiscardUnknown: true}).Unmarshal(marshaled, &req); err != nil {
+				return nil, err
+			}
+
+			resp, err := client.ListDevices(ctx, &req)
+			if err != nil {
+				return runtime.HandleError(err)
+			}
+
+			structured, err := runtime.EncodeMessage(resp)
+			if err != nil {
+				return nil, err
+			}
+			return runtime.NewToolResultJSON(structured), nil
+		})
+	}
+}

buf.gen.yaml

@@ -24,5 +24,9 @@ plugins:
     opt:
       - merge_file_name=econet-exporter
       - allow_merge=true
+  - local: ["go", "run", "github.com/redpanda-data/protoc-gen-go-mcp/cmd/protoc-gen-go-mcp@latest"]
+    out: api
+    opt:
+      - paths=source_relative
 inputs:
   - directory: proto

buf.lock

@@ -2,8 +2,8 @@
 version: v2
 deps:
   - name: buf.build/bufbuild/protovalidate
-    commit: 50325440f8f24053b047484a6bf60b76
-    digest: b5:74cb6f5c0853c3c10aafc701614194bbd63326bdb8ef4068214454b8894b03ba4113e04b3a33a8321cdf05336e37db4dc14a5e2495db8462566914f36086ba31
+    commit: 435963d1631043e694e56e6bcc3c79c3
+    digest: b5:f4ea07ad2dd94bd7243562f9908b9fb104feef8076040c89d9f7c1dedc074de4d4ce2b997686ef4400f3eccb765a7cfc20ed4acdd70b9a3699351245c61dba97
   - name: buf.build/googleapis/googleapis
     commit: c17df5b2beca46928cc87d5656bd5343
     digest: b5:648a01e0170d4512dea7d564016165decd1ed6e34bef79fe54753e51ad7e27545709ad9157d7551270147d551155c595a2fb0bf5bb33b1c83040ddbce915c604

go.mod

@@ -1,12 +1,14 @@
 module gitea.libretechconsulting.com/rmcguire/econet-exporter
 
-go 1.26
+go 1.26.1
 
 require (
 	buf.build/gen/go/bufbuild/protovalidate/protocolbuffers/go v1.36.11-20260415201107-50325440f8f2.1
+	connectrpc.com/connect v1.20.0
 	gitea.libretechconsulting.com/rmcguire/go-app v0.17.1
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.29.0
 	github.com/modelcontextprotocol/go-sdk v1.6.1
+	github.com/redpanda-data/protoc-gen-go-mcp v0.0.0-20260709214304-372b2d56e470
 	github.com/rs/zerolog v1.35.1
 	go.opentelemetry.io/otel/metric v1.44.0
 	go.opentelemetry.io/otel/trace v1.44.0
@@ -36,6 +38,7 @@ require (
 )
 
 require (
+	buf.build/gen/go/redpandadata/common/protocolbuffers/go v1.34.2-20240917150400-3f349e63f44a.2 // indirect
 	buf.build/go/protovalidate v1.2.0 // indirect
 	cel.dev/expr v0.25.2 // indirect
 	github.com/antlr4-go/antlr/v4 v4.13.1 // indirect
@@ -55,6 +58,7 @@ require (
 	github.com/prometheus/common v0.69.0 // indirect
 	github.com/prometheus/otlptranslator v1.0.0 // indirect
 	github.com/prometheus/procfs v0.21.1 // indirect
+	github.com/redpanda-data/common-go/api v0.0.0-20250801174835-9eea07f1ea06 // indirect
 	github.com/rs/cors v1.11.1 // indirect
 	github.com/segmentio/asm v1.2.1 // indirect
 	github.com/segmentio/encoding v0.5.4 // indirect

go.sum

@@ -1,9 +1,13 @@
 buf.build/gen/go/bufbuild/protovalidate/protocolbuffers/go v1.36.11-20260415201107-50325440f8f2.1 h1:s6hzCXtND/ICdGPTMGk7C+/BFlr2Jg5GyH0NKf4XGXg=
 buf.build/gen/go/bufbuild/protovalidate/protocolbuffers/go v1.36.11-20260415201107-50325440f8f2.1/go.mod h1:tvtbpgaVXZX4g6Pn+AnzFycuRK3MOz5HJfEGeEllXYM=
+buf.build/gen/go/redpandadata/common/protocolbuffers/go v1.34.2-20240917150400-3f349e63f44a.2 h1:JyGBchZNUPlQ7/qjieeKq/Cy+/i1vc0H+cIniGZNSFg=
+buf.build/gen/go/redpandadata/common/protocolbuffers/go v1.34.2-20240917150400-3f349e63f44a.2/go.mod h1:wThyg02xJx4K/DA5fg0QlKts8XVPyTT86JC8hPfEzno=
 buf.build/go/protovalidate v1.2.0 h1:DQVrUWkmGTBij+kOYv/x2LLxwcLaGKMdzShj1/6/3H0=
 buf.build/go/protovalidate v1.2.0/go.mod h1:7rYiQEhqvAipoazpVNBBH2S2f8bjG4huMVy1V2Yofn4=
 cel.dev/expr v0.25.2 h1:K6j46C81hXtZQfuX60cVWQFBJahKSE2gfRbNuvr5bFs=
 cel.dev/expr v0.25.2/go.mod h1:hrXvqGP6G6gyx8UAHSHJ5RGk//1Oj5nXQ2NI02Nrsg4=
+connectrpc.com/connect v1.20.0 h1:6TNDAB+WeNd2uolWNlYczB5E0KNNaVMNUEx8JEUsPmQ=
+connectrpc.com/connect v1.20.0/go.mod h1:A2ygJrukXwWy32vkCAAHNVguZrqZ+jeZ9rGRnGR4dN4=
 gitea.libretechconsulting.com/rmcguire/go-app v0.17.1 h1:OdUNAXRoDpB5sC3KdaJC7Rav8MmxiRZC0fRx9YNH1Ks=
 gitea.libretechconsulting.com/rmcguire/go-app v0.17.1/go.mod h1:YBygVa9JBYAP+ibF8FevN1KUe3h5GHWxAdFyU6I8QgA=
 github.com/antlr4-go/antlr/v4 v4.13.1 h1:SqQKkuVZ+zWkMMNkjy5FZe5mr5WURWnlpmOuzYWrPrQ=
@@ -65,6 +69,8 @@ github.com/modelcontextprotocol/go-sdk v1.6.1 h1:0zOSupjKUxPKSocPT1Wtago+mUHU2/u
 github.com/modelcontextprotocol/go-sdk v1.6.1/go.mod h1:kzm3kzFL1/+AziGOE0nUs3gvPoNxMCvkxokMkuFapXQ=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
+github.com/onsi/gomega v1.37.0 h1:CdEG8g0S133B4OswTDC/5XPSzE1OeP29QOioj2PID2Y=
+github.com/onsi/gomega v1.37.0/go.mod h1:8D9+Txp43QWKhM24yyOBEdpkzN8FvJyAwecBgsU4KU0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_golang v1.23.2 h1:Je96obch5RDVy3FDMndoUsjAhG5Edi49h0RJWRi/o0o=
@@ -77,6 +83,10 @@ github.com/prometheus/otlptranslator v1.0.0 h1:s0LJW/iN9dkIH+EnhiD3BlkkP5QVIUVEo
 github.com/prometheus/otlptranslator v1.0.0/go.mod h1:vRYWnXvI6aWGpsdY/mOT/cbeVRBlPWtBNDb7kGR3uKM=
 github.com/prometheus/procfs v0.21.1 h1:GljZCt+zSTS+NZq88cyQ1LjZ+RCHp3uVuabBWA5+OJI=
 github.com/prometheus/procfs v0.21.1/go.mod h1:aB55Cww9pdSJVHk0hUf0inxWyyjPogFIjmHKYgMKmtY=
+github.com/redpanda-data/common-go/api v0.0.0-20250801174835-9eea07f1ea06 h1:9Ecc+Cg1EyqSTIQ6wQKoKk8BqDlBQmR74bJui4qIqsM=
+github.com/redpanda-data/common-go/api v0.0.0-20250801174835-9eea07f1ea06/go.mod h1:klAmWfc8Q3hEZk8geFTMu6f2sk3VUKRS7cv/LvB05ig=
+github.com/redpanda-data/protoc-gen-go-mcp v0.0.0-20260709214304-372b2d56e470 h1:gBvQBXc+MtBa8aGjXTOFLPu+1a+7I0UMu6Np9ofY1Ow=
+github.com/redpanda-data/protoc-gen-go-mcp v0.0.0-20260709214304-372b2d56e470/go.mod h1:1Ulz0OS7NpChjyMu6NWZucui6SEbIsOzAshGfpqWCV8=
 github.com/rodaine/protogofakeit v0.1.1 h1:ZKouljuRM3A+TArppfBqnH8tGZHOwM/pjvtXe9DaXH8=
 github.com/rodaine/protogofakeit v0.1.1/go.mod h1:pXn/AstBYMaSfc1/RqH3N82pBuxtWgejz1AlYpY1mI0=
 github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=

pkg/econet/econet.go

@@ -16,7 +16,11 @@ import (
 	"gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/config"
 	"gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/econet/econetclient"
 	"gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/econet/econetgrpc"
-	"gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/econet/econetmcp"
+	// MCP server. Aliased so switching implementations is a one-line change.
+	// Generated (protoc-gen-go-mcp) tools:
+	econetmcp "gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/econet/econetmcpgen"
+	// Hand-written tools (switch back by using this import instead):
+	// econetmcp "gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/econet/econetmcp"
 	"gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/econet/econetmetrics"
 	"gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/service"
 )

pkg/econet/econetmcpgen/server.go

@@ -0,0 +1,72 @@
+/*
+Package econetmcpgen exposes an MCP server, mounted as an HTTP handler at
+/api/mcp, whose tools are generated from the EconetService proto by
+protoc-gen-go-mcp and forwarded to the in-process gRPC server.
+
+It is the generated-code counterpart to econetmcp (which hand-writes a single
+list_water_heaters tool). Both expose an identical package API, so switching
+between them is a one-line import change in pkg/econet/econet.go.
+*/
+package econetmcpgen
+
+import (
+	"context"
+	"net/http"
+
+	"gitea.libretechconsulting.com/rmcguire/go-app/pkg/srv/http/opts"
+	"github.com/modelcontextprotocol/go-sdk/mcp"
+	"github.com/redpanda-data/protoc-gen-go-mcp/pkg/runtime/gosdk"
+	"github.com/rs/zerolog"
+
+	v1alpha1mcp "gitea.libretechconsulting.com/rmcguire/econet-exporter/api/econet/v1alpha1/v1alpha1mcp"
+	"gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/config"
+	"gitea.libretechconsulting.com/rmcguire/econet-exporter/pkg/econet/econetgrpc"
+)
+
+var EconetMCPImpl = &mcp.Implementation{
+	Name:  "Econet MCP Server",
+	Title: "Econet Exporter MCP",
+}
+
+type EconetMCPServer struct {
+	ctx        context.Context
+	cfg        *config.ServiceConfig
+	log        *zerolog.Logger
+	server     *mcp.Server
+	econetGRPC *econetgrpc.EconetGRPCServer
+}
+
+func NewEconetMCPServer(ctx context.Context, cfg *config.ServiceConfig,
+	grpc *econetgrpc.EconetGRPCServer,
+) *EconetMCPServer {
+	return &EconetMCPServer{
+		ctx:        ctx,
+		cfg:        cfg,
+		log:        zerolog.Ctx(ctx),
+		econetGRPC: grpc,
+		server: mcp.NewServer(EconetMCPImpl, &mcp.ServerOptions{
+			Instructions: "Use these tools to inspect Rheem EcoNet water heaters: " +
+				"current mode, setpoint, hot water availability, connectivity, and alerts.",
+			HasTools: true,
+		}),
+	}
+}
+
+func (m *EconetMCPServer) GetHandlers() []opts.HTTPHandler {
+	// Register the generated tools against the in-process gRPC server via the
+	// go-sdk adapter, so the generated code shares our configured *mcp.Server.
+	v1alpha1mcp.RegisterEconetServiceHandler(gosdk.Wrap(m.server), m.econetGRPC)
+
+	handler := mcp.NewStreamableHTTPHandler(func(*http.Request) *mcp.Server {
+		return m.server
+	}, &mcp.StreamableHTTPOptions{})
+
+	m.log.Debug().Msg("Econet MCP tools ready (generated)")
+
+	return []opts.HTTPHandler{
+		{
+			Prefix:  "/api/mcp",
+			Handler: handler,
+		},
+	}
+}