fix(providers): rotate the deprecated OpenCode Zen mimo-v2.5-free id to v2.6 flash (#17472)

changelog.d/fixes/17788-opencode-zen-mimo-v2.5-free-deprecated.md

@@ -0,0 +1 @@
+- **fix(providers):** OpenCode Zen's free `mimo-v2.5-free` id is deprecated upstream (`410 Model mimo-v2.5-free has been deprecated. Use mimo-v2.6-flash-free instead.`), but it was still an active candidate, so Auto could keep selecting a model the upstream refuses. The Zen registry now advertises `mimo-v2.6-flash-free` and keeps the old id as a compatibility alias, the free-model catalog lists the replacement, and clients pinned to `mimo-v2.5-free` are forwarded to the supported id by the built-in deprecation table — the same rotation recipe as the DeepSeek V4 → V4.1 free snapshot. ([#17788](https://github.com/diegosouzapw/OmniRoute/pull/17788)) - thanks @skygunner

open-sse/config/providers/registry/opencode/zen/index.ts

@@ -197,13 +197,16 @@ export const opencode_zenProvider: RegistryEntry = {
       contextLength: 330000,
       maxOutputTokens: 128000,
     },
-    { id: "mimo-v2.5-free", name: "MiMo V2.5 Free", contextLength: 1048576 },
     // MiMo V2.6 Flash Free ships a 1M window upstream (same as V2.5); without
     // this row it falls through to the 200000 provider default and clients
     // compact far too early.
+    // 2026-10-21 sync: mimo-v2.5-free was deprecated upstream (410 "Model
+    // mimo-v2.5-free has been deprecated. Use mimo-v2.6-flash-free instead.") and
+    // replaced by mimo-v2.6-flash-free; keep the old id as a compatibility alias.
     {
       id: "mimo-v2.6-flash-free",
       name: "MiMo V2.6 Flash Free",
+      aliases: ["mimo-v2.5-free"],
       contextLength: 1048576,
       maxOutputTokens: 131072,
     },

open-sse/executors/opencodeFreeTierContract.ts

@@ -117,12 +117,13 @@ interface OpencodeFreeCatalog {
  * Legacy free ids kept only as the unsynced-catalog fallback (see the block above).
  *
  * `deepseek-v4.1-flash-free` replaced the delisted `deepseek-v4-flash-free` in the zen
- * registry; the rotating `-free` ids are covered by the suffix rule alongside this set.
+ * registry and `mimo-v2.6-flash-free` replaced the deprecated `mimo-v2.5-free`; the
+ * rotating `-free` ids are covered by the suffix rule alongside this set.
  */
 const OPENCODE_LEGACY_FREE_MODELS = new Set([
   "big-pickle",
   "deepseek-v4.1-flash-free",
-  "mimo-v2.5-free",
+  "mimo-v2.6-flash-free",
   "hy3-free",
   "nemotron-3-ultra-free",
   "north-mini-code-free",

open-sse/services/modelDeprecation.ts

@@ -61,6 +61,12 @@ const BUILT_IN_ALIASES: Record<string, string> = {
   // `400 Model is unavailable`. Clients pinned to the old id keep working.
   "deepseek-v4-flash-free": "deepseek-v4.1-flash-free",
 
+  // OpenCode Zen deprecated its free MiMo V2.5 snapshot on 2026-10-21: the
+  // upstream answers the old id with `410 Model mimo-v2.5-free has been
+  // deprecated. Use mimo-v2.6-flash-free instead.` Clients pinned to the old id
+  // keep working.
+  "mimo-v2.5-free": "mimo-v2.6-flash-free",
+
   // Mistral short aliases
   "mistral-large": "mistral-large-latest",
   "mistral-small": "mistral-small-latest",

tests/integration/freeModelBenchmarkShared.ts

@@ -178,8 +178,8 @@ export const FREE_MODELS: FreeModelSpec[] = [
   { provider: "opencode", model: "opencode/big-pickle", displayName: "Big Pickle (OpenCode)" },
   {
     provider: "opencode",
-    model: "opencode/mimo-v2.5-free",
-    displayName: "MiMo V2.5 Free (OpenCode)",
+    model: "opencode/mimo-v2.6-flash-free",
+    displayName: "MiMo V2.6 Flash Free (OpenCode)",
   },
 ];
 
@@ -209,7 +209,7 @@ export const NEWLY_ENABLED_MODELS: FreeModelSpec[] = FREE_MODELS.filter((m) =>
     "opencode/north-mini-code-free",
     "opencode/laguna-s-2.1-free",
     "opencode/big-pickle",
-    "opencode/mimo-v2.5-free",
+    "opencode/mimo-v2.6-flash-free",
   ].includes(m.model)
 );
 

tests/integration/liveDefaultComboShared.ts

@@ -50,7 +50,7 @@ async function apiFetch(path: string, options: RequestInit = {}): Promise<Respon
 // always what gets read and tested — this list never overrides it.
 const FALLBACK_COMBO_MODELS: { model: string; providerId: string }[] = [
   { model: "opencode/big-pickle", providerId: "opencode" },
-  { model: "opencode/mimo-v2.5-free", providerId: "opencode" },
+  { model: "opencode/mimo-v2.6-flash-free", providerId: "opencode" },
   { model: "opencode/laguna-s-2.1-free", providerId: "opencode" },
   { model: "openrouter/cohere/north-mini-code:free", providerId: "openrouter" },
   { model: "openrouter/poolside/laguna-m.1:free", providerId: "openrouter" },

tests/unit/opencode-mimo-v2.5-free-alias.test.ts

@@ -0,0 +1,48 @@
+import assert from "node:assert/strict";
+import { test } from "node:test";
+
+import { FREE_MODEL_BUDGETS } from "../../open-sse/config/freeModelCatalog.data.ts";
+import { opencode_zenProvider } from "../../open-sse/config/providers/registry/opencode/zen/index.ts";
+import { resolveModelAlias } from "../../open-sse/services/modelDeprecation.ts";
+
+/**
+ * OpenCode Zen deprecated `mimo-v2.5-free`: the upstream answers the old id
+ * with `410 Model mimo-v2.5-free has been deprecated. Use mimo-v2.6-flash-free
+ * instead.` Pinned clients must be forwarded to the replacement, and the
+ * deprecated id must not stay in the advertised candidate catalog.
+ */
+test("deprecated mimo-v2.5-free forwards to mimo-v2.6-flash-free for opencode-zen", () => {
+  assert.equal(resolveModelAlias("mimo-v2.5-free", "opencode-zen"), "mimo-v2.6-flash-free");
+  assert.equal(resolveModelAlias("mimo-v2.5-free", "opencode"), "mimo-v2.6-flash-free");
+  assert.equal(resolveModelAlias("mimo-v2.5-free"), "mimo-v2.6-flash-free");
+});
+
+test("the replacement id is not rewritten", () => {
+  assert.equal(resolveModelAlias("mimo-v2.6-flash-free", "opencode-zen"), "mimo-v2.6-flash-free");
+});
+
+test("opencode-zen registry advertises v2.6 flash and keeps the old id as an alias", () => {
+  const replacement = opencode_zenProvider.models.find(
+    (model) => model.id === "mimo-v2.6-flash-free"
+  );
+  assert.ok(replacement, "registry must list mimo-v2.6-flash-free");
+  assert.deepEqual(replacement.aliases, ["mimo-v2.5-free"]);
+  assert.equal(
+    opencode_zenProvider.models.some((model) => model.id === "mimo-v2.5-free"),
+    false,
+    "the deprecated id must not remain a standalone catalog row"
+  );
+});
+
+test("free-model catalog lists v2.6 flash instead of the deprecated id", () => {
+  assert.ok(
+    FREE_MODEL_BUDGETS.some(
+      (entry) =>
+        entry.provider === "opencode-zen" && entry.modelId === "opencode/mimo-v2.6-flash-free"
+    )
+  );
+  assert.equal(
+    FREE_MODEL_BUDGETS.some((entry) => entry.modelId === "opencode/mimo-v2.5-free"),
+    false
+  );
+});

tests/unit/opencode-mimo-v2.5-free-chatcore-forward-17788.test.ts

@@ -0,0 +1,74 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+
+const TEST_DATA_DIR = fs.mkdtempSync(path.join(os.tmpdir(), "omniroute-mimo-forward-17788-"));
+process.env.DATA_DIR = TEST_DATA_DIR;
+process.env.API_KEY_SECRET = process.env.API_KEY_SECRET || "mimo-forward-17788-secret";
+
+const core = await import("../../src/lib/db/core.ts");
+const { handleChatCore } = await import("../../open-sse/handlers/chatCore.ts");
+
+const originalFetch = globalThis.fetch;
+
+test.after(() => {
+  globalThis.fetch = originalFetch;
+  core.resetDbInstance();
+  fs.rmSync(TEST_DATA_DIR, { recursive: true, force: true, maxRetries: 5, retryDelay: 100 });
+});
+
+/**
+ * #17472 / #17788: OpenCode Zen answers the retired `mimo-v2.5-free` id with
+ * `410 ... Use mimo-v2.6-flash-free instead.` A client pinned to the old id must
+ * reach the upstream under the replacement id through the real chatCore path.
+ */
+for (const provider of ["opencode-zen", "opencode"]) {
+  test(`chatCore forwards a ${provider} request pinned to mimo-v2.5-free as mimo-v2.6-flash-free`, async () => {
+    const sentModels: unknown[] = [];
+    globalThis.fetch = async (_url: unknown, init?: RequestInit) => {
+      const parsed = JSON.parse(String(init?.body ?? "{}")) as Record<string, unknown>;
+      sentModels.push(parsed.model);
+      return new Response(
+        JSON.stringify({
+          id: "chatcmpl-1",
+          object: "chat.completion",
+          created: 1,
+          model: parsed.model,
+          choices: [
+            { index: 0, message: { role: "assistant", content: "ok" }, finish_reason: "stop" },
+          ],
+          usage: { prompt_tokens: 1, completion_tokens: 1, total_tokens: 2 },
+        }),
+        { status: 200, headers: { "content-type": "application/json" } }
+      );
+    };
+
+    try {
+      const body = {
+        model: "mimo-v2.5-free",
+        stream: false,
+        messages: [{ role: "user", content: "hello" }],
+      };
+      const result = await handleChatCore({
+        body: structuredClone(body),
+        modelInfo: { provider, model: "mimo-v2.5-free", extendedContext: false },
+        credentials: { apiKey: "sk-test", providerSpecificData: {} },
+        log: { debug() {}, info() {}, warn() {}, error() {} },
+        clientRawRequest: {
+          endpoint: "/v1/chat/completions",
+          body: structuredClone(body),
+          headers: new Headers({ accept: "application/json" }),
+        },
+        userAgent: "mimo-forward-17788-test",
+      });
+
+      assert.equal(result.success, true, "request must not be rejected as a retired model");
+      assert.deepEqual(sentModels, ["mimo-v2.6-flash-free"]);
+      await result.response?.body?.cancel?.().catch(() => {});
+    } finally {
+      globalThis.fetch = originalFetch;
+    }
+  });
+}