feat: introduce tool filter

Signed-off-by: Calum Murray <[email protected]>

Author: Cali0707

pkg/mcp/tool_filter.go

@@ -0,0 +1,38 @@
+package mcp
+
+import (
+	"github.com/containers/kubernetes-mcp-server/pkg/api"
+	"github.com/containers/kubernetes-mcp-server/pkg/kubernetes"
+)
+
+type ToolFilter func(tool api.ServerTool) bool
+
+func CompositeFilter(filters ...ToolFilter) ToolFilter {
+	return func(tool api.ServerTool) bool {
+		for _, f := range filters {
+			if !f(tool) {
+				return false
+			}
+		}
+
+		return true
+	}
+}
+
+func ShouldIncludeTargetListTool(targetName string, targets []string) ToolFilter {
+	return func(tool api.ServerTool) bool {
+		if tool.Tool.Name == "contexts_list" {
+			if targetName != kubernetes.KubeConfigTargetParameterName {
+				// let's not include contexts_list if we aren't targetting contexts in our ManagerProvider
+				return false
+			}
+
+			if len(targets) <= maxTargetsInEnum {
+				// all targets in enum, no need for contexts_list tool
+				return false
+			}
+		}
+
+		return true
+	}
+}