feat: add the mcp scope resource

server/internal/services/scopes.go

@@ -11,7 +11,7 @@ import (
 // the vocabulary below.
 var ErrInvalidScope = errors.New("invalid scope")
 
-// ScopeResources is the whole vocabulary. Eight resources, each with :read and
+// ScopeResources is the whole vocabulary. Ten resources, each with :read and
 // :write, and write implies read on the same resource.
 //
 // It is deliberately coarse. A scope per endpoint is a table nobody maintains,
@@ -27,6 +27,10 @@ var ScopeResources = []string{
 	"workloads",
 	"settings",
 	"status",
+	// mcp:read is permission to reach the MCP endpoint at all; mcp:write is
+	// permission for its write tools, which are not merely refused without it
+	// but omitted from tools/list entirely.
+	"mcp",
 }
 
 const (

server/internal/services/scopes_test.go

@@ -0,0 +1,43 @@
+package services
+
+import "testing"
+
+// The MCP endpoint is reached with an ordinary scope from the ordinary
+// vocabulary. A bespoke action verb here would be the first exception in a
+// table whose whole value is having none.
+func TestMCPScopesExist(t *testing.T) {
+	if err := ValidScopes([]string{"mcp:read"}); err != nil {
+		t.Errorf("ValidScopes(mcp:read) = %v, want nil", err)
+	}
+	if err := ValidScopes([]string{"mcp:write"}); err != nil {
+		t.Errorf("ValidScopes(mcp:write) = %v, want nil", err)
+	}
+	if err := ValidScopes([]string{"mcp:use"}); err == nil {
+		t.Error("ValidScopes(mcp:use) = nil, want an error")
+	}
+}
+
+// Write implies read on the same resource, so a token minted with mcp:write
+// alone still reaches the endpoint.
+func TestMCPWriteImpliesRead(t *testing.T) {
+	if !ScopeSatisfied([]string{"mcp:write"}, "mcp:read") {
+		t.Error("mcp:write does not satisfy mcp:read")
+	}
+	if ScopeSatisfied([]string{"mcp:read"}, "mcp:write") {
+		t.Error("mcp:read satisfies mcp:write, want false")
+	}
+}
+
+func TestAllScopesAdvertisesMCP(t *testing.T) {
+	want := map[string]bool{"mcp:read": false, "mcp:write": false}
+	for _, s := range AllScopes() {
+		if _, ok := want[s]; ok {
+			want[s] = true
+		}
+	}
+	for s, found := range want {
+		if !found {
+			t.Errorf("AllScopes() is missing %q", s)
+		}
+	}
+}