evcc-io · andig · Jun 19, 2025 · Jun 19, 2025 · Jun 19, 2025 · Jun 19, 2025
diff --git a/cmd/root.go b/cmd/root.go
@@ -14,6 +14,7 @@ import (
 
 	"github.com/evcc-io/evcc/core"
 	"github.com/evcc-io/evcc/core/keys"
+	"github.com/evcc-io/evcc/mcp"
 	"github.com/evcc-io/evcc/push"
 	"github.com/evcc-io/evcc/server"
 	"github.com/evcc-io/evcc/server/updater"
@@ -322,6 +323,8 @@ func runRoot(cmd *cobra.Command, args []string) {
 
 		httpd.RegisterSiteHandlers(site, valueChan)
 
+		httpd.RegisterMcpHandler(mcp.NewHandler(site))
+
 		go func() {
 			site.Run(stopC, conf.Interval)
 		}()

diff --git a/go.mod b/go.mod
@@ -67,6 +67,7 @@ require (
 	github.com/lorenzodonini/ocpp-go v0.19.0
 	github.com/lunixbochs/struc v0.0.0-20241101090106-8d528fa2c543
 	github.com/mabunixda/wattpilot v1.8.4
+	github.com/mark3labs/mcp-go v0.32.0
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/muka/go-bluetooth v0.0.0-20240701044517-04c4f09c514e
 	github.com/mxschmitt/golang-combinations v1.2.0
@@ -205,6 +206,7 @@ require (
 	github.com/teivah/onecontext v1.3.0 // indirect
 	github.com/vmihailenco/msgpack/v5 v5.4.1 // indirect
 	github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect
+	github.com/yosida95/uritemplate/v3 v3.0.2 // indirect
 	gitlab.com/c0b/go-ordered-json v0.0.0-20201030195603-febf46534d5a // indirect
 	go.uber.org/multierr v1.11.0 // indirect
 	golang.org/x/mod v0.24.0 // indirect

diff --git a/go.sum b/go.sum
@@ -435,6 +435,8 @@ github.com/lunixbochs/struc v0.0.0-20241101090106-8d528fa2c543/go.mod h1:vy1vK6w
 github.com/lyft/protoc-gen-validate v0.0.13/go.mod h1:XbGvPuh87YZc5TdIa2/I4pLk0QoUACkjt2znoq26NVQ=
 github.com/mabunixda/wattpilot v1.8.4 h1:nPwTQft15JeRJDUoxv6IpsGpu45EvNGW3EFU6UHNUzc=
 github.com/mabunixda/wattpilot v1.8.4/go.mod h1:oXWlvKInaVt8FFSdEoNObEP5N8+4m6cbiF11M+8DAHY=
+github.com/mark3labs/mcp-go v0.32.0 h1:fgwmbfL2gbd67obg57OfV2Dnrhs1HtSdlY/i5fn7MU8=
+github.com/mark3labs/mcp-go v0.32.0/go.mod h1:rXqOudj/djTORU/ThxYx8fqEVj/5pvTuuebQ2RC7uk4=
 github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
 github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
@@ -710,6 +712,8 @@ github.com/volkszaehler/mbmd v0.0.0-20250524200024-23178706aaf1/go.mod h1:egeAZt
 github.com/writeas/go-strip-markdown/v2 v2.1.1 h1:hAxUM21Uhznf/FnbVGiJciqzska6iLei22Ijc3q2e28=
 github.com/writeas/go-strip-markdown/v2 v2.1.1/go.mod h1:UvvgPJgn1vvN8nWuE5e7v/+qmDu3BSVnKAB6Gl7hFzA=
 github.com/xiang90/probing v0.0.0-20190116061207-43a291ad63a2/go.mod h1:UETIi67q53MR2AWcXfiuqkDkRtnGDLqkBTpCHuJHxtU=
+github.com/yosida95/uritemplate/v3 v3.0.2 h1:Ed3Oyj9yrmi9087+NczuL5BwkIc4wvTb5zIM+UJPGz4=
+github.com/yosida95/uritemplate/v3 v3.0.2/go.mod h1:ILOh0sOhIJR3+L/8afwt/kE++YT040gmv5BQTMR2HP4=
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 gitlab.com/bboehmke/sunny v0.16.0 h1:arcU5MNupJ9KELOcSC82mYPGP/friBop+PxtybhqRwo=
8000
diff --git a/mcp/helper.go b/mcp/helper.go
@@ -0,0 +1,24 @@
+package mcp
+
+import (
+	"strconv"
+	"strings"
+)
+
+func extractID(uri string) string {
+	// Extract the ID from the URI, e.g., "loadpoints://123" -> "123"
+	parts := strings.Split(uri, "://")
+	if len(parts) < 2 {
+		return ""
+	}
+	return parts[1]
+}
+
+func extractNumericID(uri string) int {
+	s := extractID(uri)
+	if s == "" {
+		return 0
+	}
+	id, _ := strconv.Atoi(s)
+	return id
+}
diff --git a/mcp/loadpoint.go b/mcp/loadpoint.go
@@ -0,0 +1,47 @@
+package mcp
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+
+	"github.com/evcc-io/evcc/api"
+	"github.com/evcc-io/evcc/core/site"
+	"github.com/mark3labs/mcp-go/mcp"
+)
+
+func loadpointStatusHandler(site site.API) func(ctx context.Context, req mcp.ReadResourceRequest) ([]mcp.ResourceContents, error) {
+	return func(ctx context.Context, req mcp.ReadResourceRequest) ([]mcp.ResourceContents, error) {
+		lpid := extractNumericID(req.Params.URI) // "users://123" -> "123"
+
+		if lpid == 0 || lpid > len(site.Loadpoints()) {
+			return nil, errors.New("invalid loadpoint ID")
+		}
+
+		lp := site.Loadpoints()[lpid-1] // Loadpoint IDs are 1-based
+		status := lp.GetStatus()
+
+		data := struct {
+			Title     string `json:"title"`
+			Connected bool   `json:"connected,omitempty"`
+			Charging  bool   `json:"charging,omitempty"`
+		}{
+			Title:     lp.GetTitle(),
+			Connected: status == api.StatusB || status == api.StatusC,
+			Charging:  status == api.StatusC,
+		}
+
+		jsonData, err := json.Marshal(data)
+		if err != nil {
+			return nil, err
+		}
+
+		return []mcp.ResourceContents{
+			mcp.TextResourceContents{
+				URI:      req.Params.URI,
+				MIMEType: "application/json",
+				Text:     string(jsonData),
+			},
+		}, nil
+	}
+}
diff --git a/mcp/log.go b/mcp/log.go
@@ -0,0 +1,15 @@
+package mcp
+
+import "github.com/evcc-io/evcc/util"
+
+type logAdapter struct {
+	log *util.Logger
+}
+
+func (l *logAdapter) Infof(format string, args ...interface{}) {
+	l.log.INFO.Printf(format, args...)
+}
+
+func (l *logAdapter) Errorf(format string, args ...interface{}) {
+	l.log.ERROR.Printf(format, args...)
+}
diff --git a/mcp/mcp.go b/mcp/mcp.go
@@ -0,0 +1,65 @@
+package mcp
+
+import (
+	"net/http"
+
+	"github.com/evcc-io/evcc/core/site"
+	"github.com/evcc-io/evcc/util"
+	"github.com/mark3labs/mcp-go/mcp"
+	"github.com/mark3labs/mcp-go/server"
+)
+
+func NewHandler(site site.API) http.Handler {
+	log := util.NewLogger("mcp")
+
+	// Create a new MCP server
+	s := server.NewMCPServer(
+		"evcc ☀️🚘",
+		util.Version,
+		server.WithToolCapabilities(true),
+	)
+
+	s.AddResource(
+		mcp.NewResource(
+			"https://docs.evcc.io",
+			"docs",
+			mcp.WithResourceDescription("evcc documentation"),
+		),
+		nil, // TODO no handler needed
+	)
+
+	s.AddTool(
+		mcp.NewTool(
+			"site-loadpoints",
+			mcp.WithDescription("Number of loadpoints"),
+			mcp.WithReadOnlyHintAnnotation(true),
+		),
+		loadpointsHandler(site),
+	)
+
+	s.AddTool(
+		mcp.NewTool(
+			"solar-forecast",
+			mcp.WithDescription("Solar forecast for remaining production today"),
+			mcp.WithReadOnlyHintAnnotation(true),
+		),
+		solarForecastHandler(site),
+	)
+
+	s.AddResource(
+		mcp.NewResource(
+			"loadpoints://{loadpoint_id}",
+			"loadpoint-status",
+			mcp.WithResourceDescription("Loadpoint status information"),
+			mcp.WithMIMEType("application/json"),
+		),
+		loadpointStatusHandler(site),
+	)
+
+	ss := server.NewStreamableHTTPServer(s,
+		server.WithLogger(&logAdapter{log}),
+		server.WithEndpointPath("/"),
+	)
+
+	return ss
+}
diff --git a/mcp/site.go b/mcp/site.go
@@ -0,0 +1,46 @@
+package mcp
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strconv"
+	"time"
+
+	"github.com/evcc-io/evcc/api"
+	"github.com/evcc-io/evcc/core/site"
+	"github.com/evcc-io/evcc/tariff"
+	"github.com/jinzhu/now"
+	"github.com/mark3labs/mcp-go/mcp"
+)
+
+func loadpointsHandler(site site.API) func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
+	return func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
+		count := len(site.Loadpoints())
+		return mcp.NewToolResultText(strconv.Itoa(count)), nil
+	}
+}
+
+func solarForecastHandler(site site.API) func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
+	return func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
+		solar := site.GetTariff(api.TariffUsageSolar)
+		if solar == nil {
+			return nil, errors.New("solar tariff not found")
+		}
+
+		rates := tariff.Forecast(solar)
+		if len(rates) == 0 {
+			return nil, errors.New("solar forecast data not available")
+		}
+
+		// TODO use global function
+		var total float64
+		for _, rate := range rates {
+			if rate.Start.After(time.Now()) && !rate.End.After(now.EndOfDay()) {
+				total += rate.Value * rate.End.Sub(rate.Start).Hours() // Wh
+			}
+		}
+
+		return mcp.NewToolResultText(fmt.Sprintf("%.2f kWH", total/1e3)), nil
+	}
+}