Add simple MCP server

Proof of concept of working MCP server for Probo. Currently the official
MCP library does not support session that why the server is configured
in stateless mode. It seams the input jsonschema is not used to perform
any validation, so we should figuring out how to validate the input
properly.

Signed-off-by: Bryan Frimin <bryan@getprobo.com>

pkg/server/api/mcp/v1/v1_handler.go

@@ -0,0 +1,209 @@
+package v1
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/getprobo/probo/pkg/gid"
+	"github.com/getprobo/probo/pkg/probo"
+	"github.com/go-chi/chi/v5"
+	"github.com/google/jsonschema-go/jsonschema"
+	"github.com/modelcontextprotocol/go-sdk/mcp"
+)
+
+type (
+	resolver struct {
+		proboSvc       *probo.TenantService
+		organizationID gid.GID
+	}
+)
+
+func NewMux(proboSvc *probo.Service) *chi.Mux {
+	server := mcp.NewServer(
+		&mcp.Implementation{
+			Name:    "probo",
+			Title:   "Probo",
+			Version: "1.0.0", // todo retrieve from build info
+		},
+		&mcp.ServerOptions{},
+	)
+
+	tenantID, err := gid.ParseTenantID("lXdXZSh-AAE")
+	if err != nil {
+		panic(err)
+	}
+
+	organizationID, err := gid.ParseGID("lXdXZSh-AAEAAAAAAZfLJi38a0AGbu37")
+	if err != nil {
+		panic(err)
+	}
+
+	resolver := &resolver{proboSvc: proboSvc.WithTenant(tenantID), organizationID: organizationID}
+
+	mcp.AddTool(
+		server,
+		&mcp.Tool{
+			Title:       "List Vendors",
+			Description: "List all vendors for the organization",
+			Name:        "listVendors",
+			Annotations: &mcp.ToolAnnotations{
+				Title:        "List Vendors",
+				ReadOnlyHint: true,
+			},
+			InputSchema: &jsonschema.Schema{
+				Type: "object",
+				Properties: map[string]*jsonschema.Schema{
+					"orderField": {
+						Type:    "string",
+						Default: json.RawMessage(`"NAME"`),
+						Enum: []any{
+							"NAME",
+							"CREATED_AT",
+							"UPDATED_AT",
+						},
+					},
+					"cursor": {
+						Type: "string",
+					},
+					"size": {
+						Type:    "integer",
+						Minimum: jsonschema.Ptr(float64(1)),
+						Maximum: jsonschema.Ptr(float64(1000)),
+						Default: json.RawMessage(`100`),
+					},
+				},
+			},
+			OutputSchema: &jsonschema.Schema{
+				Type: "object",
+				Properties: map[string]*jsonschema.Schema{
+					"result": {
+						Type: "array",
+						Items: &jsonschema.Schema{
+							Type:     "object",
+							Required: []string{"name", "id"},
+							Properties: map[string]*jsonschema.Schema{
+								"name": {
+									Type: "string",
+								},
+								"id": {
+									Type: "string",
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+		resolver.ListVendors,
+	)
+
+	mcp.AddTool(
+		server,
+		&mcp.Tool{
+			Name:        "addVendor",
+			Description: "Add a vendor",
+			InputSchema: &jsonschema.Schema{
+				Type: "object",
+				Properties: map[string]*jsonschema.Schema{
+					"name": {
+						Type:     "string",
+						Required: []string{"name"},
+					},
+					"description": {
+						Type: "string",
+					},
+					"headquarterAddress": {
+						Type: "string",
+					},
+					"legalName": {
+						Type: "string",
+					},
+					"websiteURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"category": {
+						Type: "string",
+					},
+					"privacyPolicyURL": {
+						Type: "string",
+					},
+					"serviceLevelAgreementURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"dataProcessingAgreementURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"businessAssociateAgreementURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"subprocessorsListURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"certifications": {
+						Type: "array",
+						Items: &jsonschema.Schema{
+							Type: "string",
+						},
+					},
+					"securityPageURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"trustPageURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"termsOfServiceURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"statusPageURL": {
+						Type:   "string",
+						Format: "uri",
+					},
+					"businessOwnerID": {
+						Type: "string",
+					},
+					"securityOwnerID": {
+						Type: "string",
+					},
+				},
+			},
+			OutputSchema: &jsonschema.Schema{
+				Type: "object",
+				Properties: map[string]*jsonschema.Schema{
+					"result": {
+						Type:     "object",
+						Required: []string{"name", "id"},
+						Properties: map[string]*jsonschema.Schema{
+							"name": {
+								Type: "string",
+							},
+							"id": {
+								Type: "string",
+							},
+						},
+					},
+				},
+			},
+		},
+		resolver.AddVendor,
+	)
+
+	getServer := func(r *http.Request) *mcp.Server { return server }
+
+	handler := mcp.NewStreamableHTTPHandler(
+		getServer,
+		&mcp.StreamableHTTPOptions{Stateless: true},
+	)
+
+	r := chi.NewMux()
+	r.Handle("/", handler)
+
+	return r
+}