diff --git a/packages/lib/src/config/definitions.ts b/packages/lib/src/config/definitions.ts
index 671eec66..cfed9f21 100644
--- a/packages/lib/src/config/definitions.ts
+++ b/packages/lib/src/config/definitions.ts
@@ -842,6 +842,10 @@ export function addPluginConfigFields(pluginInfos: PluginNodeEnvInfo[] | PluginW
 		if (pluginInfo.instanceEntrypoint) {
 			addPluginFieldDefinitions(pluginInfo, "instanceConfigFields", InstanceConfig);
 		}
+		if (pluginInfo.ctlConfigFields) {
+			validateFieldNames(pluginInfo.name, pluginInfo.ctlConfigFields);
+			Object.assign(CtlConfig.fieldDefinitions, pluginInfo.ctlConfigFields);
+		}
 	}
 }
 
diff --git a/test/lib/config/definitions.js b/test/lib/config/definitions.js
new file mode 100644
index 00000000..a406f579
--- /dev/null
+++ b/test/lib/config/definitions.js
@@ -0,0 +1,30 @@
+import assert from "node:assert/strict";
+
+import * as lib from "@clusterio/lib";
+
+
+describe("lib/config/definitions", function() {
+	describe("addPluginConfigFields()", function() {
+		after(function() {
+			delete lib.CtlConfig.fieldDefinitions["ctl_test.field"];
+		});
+
+		it("should add ctl config fields", function() {
+			lib.addPluginConfigFields([{
+				name: "ctl_test",
+				ctlConfigFields: { "ctl_test.field": { type: "string", initialValue: "value" } },
+			}]);
+			const config = new lib.CtlConfig("control");
+			assert.equal(config.get("ctl_test.field"), "value");
+		});
+		it("should reject ctl config fields not named after the plugin", function() {
+			assert.throws(
+				() => lib.addPluginConfigFields([{
+					name: "ctl_test",
+					ctlConfigFields: { "other.field": { type: "string" } },
+				}]),
+				new Error("Expected name of config field 'other.field' for ctl_test to start with 'ctl_test.'")
+			);
+		});
+	});
+});