diff --git a/cmd/api/cmd_sdk.go b/cmd/api/cmd_sdk.go
index c8c0b0a..1bc2e07 100644
--- a/cmd/api/cmd_sdk.go
+++ b/cmd/api/cmd_sdk.go
@@ -39,7 +39,7 @@ func addSDKCommand(parent *cli.Command) {
 			}
 
 			bridge := goapi.NewToolBridge("/tools")
-			groups := []goapi.RouteGroup{bridge}
+			groups := append(goapi.RegisteredSpecGroups(), bridge)
 
 			tmpFile, err := os.CreateTemp("", "openapi-*.json")
 			if err != nil {
diff --git a/cmd/api/cmd_spec.go b/cmd/api/cmd_spec.go
index 97b3033..782340f 100644
--- a/cmd/api/cmd_spec.go
+++ b/cmd/api/cmd_spec.go
@@ -22,8 +22,7 @@ func addSpecCommand(parent *cli.Command) {
 	)
 
 	cmd := cli.NewCommand("spec", "Generate OpenAPI specification", "", func(cmd *cli.Command, args []string) error {
-		// Build spec from registered route groups.
-		// Additional groups can be added here as the platform grows.
+		// Build spec from all route groups registered for CLI generation.
 		builder := &goapi.SpecBuilder{
 			Title:       title,
 			Description: description,
@@ -31,11 +30,8 @@ func addSpecCommand(parent *cli.Command) {
 			Servers:     parseServers(servers),
 		}
 
-		// Start with the default tool bridge — future versions will
-		// auto-populate from the MCP tool registry once the bridge
-		// integration lands in the local go-ai module.
 		bridge := goapi.NewToolBridge("/tools")
-		groups := []goapi.RouteGroup{bridge}
+		groups := append(goapi.RegisteredSpecGroups(), bridge)
 
 		if output != "" {
 			if err := goapi.ExportSpecToFile(output, format, builder, groups); err != nil {
diff --git a/cmd/api/cmd_test.go b/cmd/api/cmd_test.go
index 778e59a..2f60b4a 100644
--- a/cmd/api/cmd_test.go
+++ b/cmd/api/cmd_test.go
@@ -8,9 +8,32 @@ import (
 	"os"
 	"testing"
 
+	"github.com/gin-gonic/gin"
+
 	"forge.lthn.ai/core/cli/pkg/cli"
+
+	api "dappco.re/go/core/api"
 )
 
+type specCmdStubGroup struct{}
+
+func (specCmdStubGroup) Name() string                       { return "registered" }
+func (specCmdStubGroup) BasePath() string                   { return "/registered" }
+func (specCmdStubGroup) RegisterRoutes(rg *gin.RouterGroup) {}
+func (specCmdStubGroup) Describe() []api.RouteDescription {
+	return []api.RouteDescription{
+		{
+			Method:  "GET",
+			Path:    "/ping",
+			Summary: "Ping registered group",
+			Tags:    []string{"registered"},
+			Response: map[string]any{
+				"type": "string",
+			},
+		},
+	}
+}
+
 func TestAPISpecCmd_Good_CommandStructure(t *testing.T) {
 	root := &cli.Command{Use: "root"}
 	AddAPICommands(root)
@@ -131,6 +154,40 @@ func TestAPISpecCmd_Good_ServerFlagAddsServers(t *testing.T) {
 	}
 }
 
+func TestAPISpecCmd_Good_RegisteredSpecGroups(t *testing.T) {
+	api.RegisterSpecGroups(specCmdStubGroup{})
+
+	root := &cli.Command{Use: "root"}
+	AddAPICommands(root)
+
+	outputFile := t.TempDir() + "/spec.json"
+	root.SetArgs([]string{"api", "spec", "--output", outputFile})
+	root.SetErr(new(bytes.Buffer))
+
+	if err := root.Execute(); err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	data, err := os.ReadFile(outputFile)
+	if err != nil {
+		t.Fatalf("expected spec file to be written: %v", err)
+	}
+
+	var spec map[string]any
+	if err := json.Unmarshal(data, &spec); err != nil {
+		t.Fatalf("expected valid JSON spec, got error: %v", err)
+	}
+
+	paths, ok := spec["paths"].(map[string]any)
+	if !ok {
+		t.Fatalf("expected paths object in generated spec, got %T", spec["paths"])
+	}
+
+	if _, ok := paths["/registered/ping"]; !ok {
+		t.Fatal("expected registered route group path in generated spec")
+	}
+}
+
 func TestAPISDKCmd_Bad_EmptyLanguages(t *testing.T) {
 	root := &cli.Command{Use: "root"}
 	AddAPICommands(root)
diff --git a/spec_registry.go b/spec_registry.go
new file mode 100644
index 0000000..610806e
--- /dev/null
+++ b/spec_registry.go
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+package api
+
+import "sync"
+
+// specRegistry stores RouteGroups that should be included in CLI-generated
+// OpenAPI documents. Packages can register their groups during init and the
+// API CLI will pick them up when building specs or SDKs.
+var specRegistry struct {
+	mu     sync.RWMutex
+	groups []RouteGroup
+}
+
+// RegisterSpecGroups adds route groups to the package-level spec registry.
+// Nil groups are ignored. Registered groups are returned by RegisteredSpecGroups
+// in the order they were added.
+func RegisterSpecGroups(groups ...RouteGroup) {
+	specRegistry.mu.Lock()
+	defer specRegistry.mu.Unlock()
+
+	for _, group := range groups {
+		if group == nil {
+			continue
+		}
+		specRegistry.groups = append(specRegistry.groups, group)
+	}
+}
+
+// RegisteredSpecGroups returns a copy of the route groups registered for
+// CLI-generated OpenAPI documents.
+func RegisteredSpecGroups() []RouteGroup {
+	specRegistry.mu.RLock()
+	defer specRegistry.mu.RUnlock()
+
+	out := make([]RouteGroup, len(specRegistry.groups))
+	copy(out, specRegistry.groups)
+	return out
+}