diff --git a/src/core/config/__tests__/routerRemoval.spec.ts b/src/core/config/__tests__/routerRemoval.spec.ts
new file mode 100644
index 0000000000..9c98661d2b
--- /dev/null
+++ b/src/core/config/__tests__/routerRemoval.spec.ts
@@ -0,0 +1,38 @@
+import { retiredProviderIdentifiers } from "@roo-code/types"
+
+import { downgradeLegacyRooConfig, isLegacyRooConfig, LEGACY_ROO_PROVIDER } from "../routerRemoval"
+
+describe("routerRemoval", () => {
+	it("uses the canonical retired Roo provider identifier without changing its persisted value", () => {
+		expect(LEGACY_ROO_PROVIDER).toBe(retiredProviderIdentifiers.roo)
+		expect(LEGACY_ROO_PROVIDER).toBe("roo")
+	})
+
+	it("continues to recognize and downgrade persisted Roo provider settings", () => {
+		const persistedConfig = {
+			apiProvider: retiredProviderIdentifiers.roo,
+			apiModelId: "roo/code-supernova",
+			rooApiKey: "legacy-key",
+			customSetting: "preserved",
+		}
+
+		expect(isLegacyRooConfig(persistedConfig)).toBe(true)
+		expect(downgradeLegacyRooConfig(persistedConfig)).toEqual({
+			config: { customSetting: "preserved" },
+			migrated: true,
+		})
+	})
+
+	it("leaves non-Roo retired provider settings unchanged", () => {
+		const persistedConfig = {
+			apiProvider: retiredProviderIdentifiers.groq,
+			apiModelId: "legacy-model",
+		}
+
+		expect(isLegacyRooConfig(persistedConfig)).toBe(false)
+		expect(downgradeLegacyRooConfig(persistedConfig)).toEqual({
+			config: persistedConfig,
+			migrated: false,
+		})
+	})
+})
diff --git a/src/core/config/routerRemoval.ts b/src/core/config/routerRemoval.ts
index a34143cc35..45d96c65d2 100644
--- a/src/core/config/routerRemoval.ts
+++ b/src/core/config/routerRemoval.ts
@@ -1,6 +1,8 @@
+import { retiredProviderIdentifiers } from "@roo-code/types"
+
 import { t } from "../../i18n"
 
-export const LEGACY_ROO_PROVIDER = "roo"
+export const LEGACY_ROO_PROVIDER = retiredProviderIdentifiers.roo
 
 const ROUTER_REMOVAL_I18N_KEY = "common:errors.roo.routerRemoved"
 const ROUTER_REMOVAL_DEFAULT_MESSAGE =