fix(providers): route OpenCode Go Gemini through its native wire

docs-site/src/content/docs/guides/providers.md

@@ -718,7 +718,21 @@ MiniMax model list is still the previous default receives it on the next start;
 is left as it is; register the preview by hand with
 `ocx models add minimax MiniMax-M3.1-Flash-Preview --context-window 1000000`.
 
-**OpenCode Go** requires a stable session identifier for routing. OpenCodex sends
+**OpenCode Go** routes `gemini-4-argon-contributor` through its Gemini API, including
+streaming and tool-result continuations. The existing `opencode-go` preset keeps its
+historical URL pinning: saved custom URLs, including `https://opencode.ai/inference/go/v1`,
+route through the canonical `https://opencode.ai/zen/go/v1` endpoint and inherit Go defaults.
+Gemini then uses Go's native model endpoint with key authentication. A differently named
+custom provider keeps its configured URL and does not receive this Gemini pin.
+Go selects protocols by exact model ID: GPT 6 Luna, GPT 5.6 Luna, Grok 4.6/4.7 and
+Muse Spark Contributor use Responses; Claude Haiku 5.5, MiniMax M2.7/M3 and
+Qwen3.7 Plus/3.8 Max/3.8 Flash use Anthropic Messages. Legacy MiniMax M2.5 and
+Union Alpha also retain Messages. Models without a listed wire retain Chat.
+New native pins apply to the pinned Go destination with key authentication.
+Responses models still accept an explicit `modelAdapters` override.
+Gemini uses `low`, `medium` and `high` thinking levels; higher requested efforts clamp to `high`.
+
+OpenCode Go requires a stable session identifier for routing. OpenCodex sends
 `claude-haiku-5-5`, like the MiniMax models, over the Anthropic Messages wire, matching
 [OpenCode Go's endpoint table](https://opencode.ai/docs/go/#endpoints). OpenCodex derives
 its Go session header from Codex thread/session headers, or from a client's

scripts/test-layout/layout.json

@@ -283,6 +283,7 @@
     "catalog-modelalias-unique-sync.test.ts": "codex-integration",
     "catalog-oauth-observation.test.ts": "codex-integration",
     "catalog-opencode-go-context-window.test.ts": "codex-integration",
+    "catalog-opencode-go-static.test.ts": "codex-integration",
     "catalog-remote-pull.test.ts": "codex-integration",
     "catalog-retain-models.test.ts": "codex-integration",
     "catalog-routed-comp-hash.test.ts": "codex-integration",
@@ -1283,6 +1284,9 @@
     "opencode-cli.test.ts": "providers",
     "opencode-free-provider.test.ts": "providers",
     "opencode-go-deepseek.test.ts": "providers",
+    "opencode-go-gemini-wire.test.ts": "providers",
+    "opencode-go-model-protocols.test.ts": "providers",
+    "registry-transport-alias.test.ts": "providers",
     "opencode-go-grok46-responses.test.ts": "providers",
     "opencode-go-luna-wire.test.ts": "providers",
     "opencode-go-muse-context.test.ts": "providers",

src/adapters/google.ts

@@ -1,6 +1,7 @@
 import type { AdapterFetchContext, AdapterRequest, ProviderAdapter } from "./base";
 import { debugDroppedFrame, debugProviderDiagnosticLazy } from "../lib/debug";
 import { createToolCallIdAllocator } from "./tool-call-id";
+import { openCodeGoGeminiEndpoint } from "../types/opencode-go";
 import { createImageBudget, materializeInlineImage, MAX_ENCODED_BYTES_PER_IMAGE, artifactHttpUrl } from "../images/artifacts";
 import type {
   AdapterEvent,
@@ -864,6 +865,7 @@ function invalidGoogleShapeEvent(
   };
 }
 
+/** Build Gemini transport and response parsing for AI Studio, Vertex, Cloud Code Assist or Go. */
 export function createGoogleAdapter(provider: OcxProviderConfig): ProviderAdapter {
   const toolSchemaPolicy = provider.googleToolSchemaPolicy ?? "compatible";
   const toolSchemaProfile = {
@@ -945,6 +947,7 @@ export function createGoogleAdapter(provider: OcxProviderConfig): ProviderAdapte
         }
       : {}),
 
+    /** Compile an admitted request into the selected Gemini endpoint, body and authentication. */
     async buildRequest(parsed: OcxParsedRequest) {
       // Structured-output admission runs FIRST, before messagesToGeminiFormat writes
       // lastInjectedCallIds/lastReasoningReplayScope: a refused request must not leave
@@ -1202,11 +1205,21 @@ export function createGoogleAdapter(provider: OcxProviderConfig): ProviderAdapte
         return { url, method: "POST", headers, body: JSON.stringify(compiled.body) };
       }
 
-      // ai-studio (default): Generative Language API + x-goog-api-key.
-      const url = `${provider.baseUrl}/v1beta/models/${routedModelId}:${method}${streamParam}`;
+      // Go speaks Gemini on its own endpoint; ordinary AI Studio keeps /v1beta and its key header.
+      const goEndpoint = openCodeGoGeminiEndpoint(provider, routedModelId);
+      const endpoint = goEndpoint ?? `${provider.baseUrl}/v1beta/models/${routedModelId}`;
+      const url = `${endpoint}:${method}${streamParam}`;
       const apiKey = provider.apiKey?.trim();
-      if (!apiKey) throw new Error("google (AI Studio) requires a non-empty API key");
-      headers["x-goog-api-key"] = apiKey;
+      if (!apiKey) throw new Error(`${goEndpoint ? "OpenCode Go" : "google (AI Studio)"} requires a non-empty API key`);
+      if (goEndpoint) {
+        // Console inference documents Bearer auth. Send only the selected Go key.
+        for (const name of Object.keys(headers)) {
+          if (["authorization", "x-goog-api-key", "x-api-key"].includes(name.toLowerCase())) delete headers[name];
+        }
+        headers["Authorization"] = `Bearer ${apiKey}`;
+      } else {
+        headers["x-goog-api-key"] = apiKey;
+      }
 
       const compiled = compileGoogleWireBody(body, toolSchemaProfile, toolSchemaPolicy);
       reportToolSchemaLoss(compiled.toolSchemaLossReport);

src/protocols/provider-summary.ts

@@ -55,12 +55,13 @@ function usableModelId(model: unknown): model is string {
 function candidateModelIds(name: string, provider: Readonly<OcxProviderConfig>): string[] {
   const registry = PROVIDER_REGISTRY.find(entry => entry.id === name);
   const ids = new Set<string>();
+  /** Collect valid candidate IDs without exceeding the protocol-summary scan limit. */
   const add = (model: unknown) => {
     if (ids.size < MODEL_SCAN_LIMIT && usableModelId(model)) ids.add(model);
   };
   for (const model of Object.keys(provider.modelAdapters ?? {})) add(model);
   for (const model of Object.keys(registry?.modelWireDefaults ?? {})) add(model);
-  for (const model of Object.keys(captureWireAdapterHardPins(name))) add(model);
+  for (const model of Object.keys(captureWireAdapterHardPins(name, provider))) add(model);
   add(provider.defaultModel);
   for (const model of provider.models ?? []) add(model);
   return [...ids].sort((left, right) => left.localeCompare(right));

src/providers/opencode-go-transport.ts

@@ -1,6 +1,7 @@
 import { createHash } from "node:crypto";
 import type { OcxProviderConfig } from "../types";
 import { registryEntryForProviderDestination } from "./registry";
+import { isOpenCodeGoGeminiDestination } from "../types/opencode-go";
 
 export const OPENCODE_GO_SESSION_HEADER = "x-opencode-session";
 
@@ -44,7 +45,8 @@ export function resolveOpenCodeGoTransport<T extends OcxProviderConfig>(
     Pick<OcxProviderConfig, "baseUrl" | "adapter">
     & Partial<Pick<OcxProviderConfig, "authMode">>,
 ): T {
-  if (registryEntryForProviderDestination(destinationProvider)?.id !== "opencode-go") return provider;
+  if (registryEntryForProviderDestination(destinationProvider)?.id !== "opencode-go"
+    && !(provider.adapter === "google" && isOpenCodeGoGeminiDestination(provider))) return provider;
   if (!sessionLane) return provider;
   if (hasHeaderCaseInsensitive(provider.headers, OPENCODE_GO_SESSION_HEADER)) return provider;
 

src/providers/registry/entries-core.ts

@@ -1,3 +1,4 @@
+import { OPENCODE_GO_BASE_URL, OPENCODE_GO_RESPONSES_DEFAULTS } from "../../types/opencode-go";
 import { KIRO_MODELS, KIRO_MODEL_CONTEXT_WINDOWS, KIRO_MODEL_REASONING_EFFORTS } from "../kiro-models";
 import { DEVIN_MODEL_CONTEXT_WINDOWS, DEVIN_MODEL_EFFORTS, DEVIN_DEFAULT_EFFORTS } from "../../adapters/devin/live-models";
 import { ANTIGRAVITY_MODELS, ANTIGRAVITY_MODEL_CONTEXT_WINDOWS, ANTIGRAVITY_MODEL_EFFORTS, ANTIGRAVITY_MODEL_INPUT_MODALITIES } from "../antigravity-models";
@@ -824,7 +825,8 @@ export const PROVIDER_REGISTRY_CORE: readonly ProviderRegistryEntry[] = [
     escapeBuiltinToolNames: true,
   },
   {
-    id: "opencode-go", label: "opencode go", adapter: "openai-chat", baseUrl: "https://opencode.ai/zen/go/v1",
+    id: "opencode-go", label: "opencode go", adapter: "openai-chat", baseUrl: OPENCODE_GO_BASE_URL,
+    destinationAliases: [{ adapter: "openai-chat", baseUrl: "https://opencode.ai/inference/go/v1" }],
     authKind: "key", featured: true, dashboardUrl: "https://opencode.ai/auth", defaultModel: "kimi-k2.7-code",
     jawcodeBundle: "opencode-go", note: "GLM, DeepSeek, Kimi, Qwen, MiMo…",
     // Zen Go can close a Chat stream after a fully assembled function call without sending
@@ -846,13 +848,7 @@ export const PROVIDER_REGISTRY_CORE: readonly ProviderRegistryEntry[] = [
     - 다른 대안 대신 이 방식을 선택한 이유: OpenCode Go documents sibling models on Chat or Anthropic endpoints, and an exact registry default preserves both those routes and explicit opt-out precedence.
     - 장점, 단점 및 영향: Each listed model reaches `/responses` from every inbound surface without changing siblings; a future upstream endpoint change requires an evidence-backed registry update.
     */
-    modelWireDefaults: {
-      "gpt-5.6-luna": "openai-responses",
-      "grok-4.6": "openai-responses",
-      "grok-4.7": "openai-responses",
-      "muse-spark-1.3-contributor": "openai-responses",
-      "muse-spark-1.2-contributor": "openai-responses",
-    },
+    modelWireDefaults: OPENCODE_GO_RESPONSES_DEFAULTS,
     modelContextWindows: {
       "kimi-k3": KIMI_K3_STANDARD_CONTEXT_WINDOW,
       // Zen Go discovers only the gateway id, so carry DeepSeek's official 1M V4.1
@@ -909,6 +905,9 @@ export const PROVIDER_REGISTRY_CORE: readonly ProviderRegistryEntry[] = [
     },
     modelReasoningEfforts: {
       "gpt-5.6-luna": OPENAI_API_GPT56_REASONING_EFFORTS,
+      // Gemini's native thinkingLevel ladder; higher Codex efforts clamp to high.
+      // https://ai.google.dev/gemini-api/docs/models/gemini-4-argon
+      "gemini-4-argon-contributor": ["low", "medium", "high"],
       "grok-4.6": ["low", "medium", "high", "xhigh"],
       "grok-4.7": ["low", "medium", "high", "xhigh"],
       "glm-5.3": ZAI_GLM_53_REASONING_EFFORTS,

src/providers/registry/types.ts

@@ -213,7 +213,7 @@ export interface ProviderRegistryEntry {
    */
   chatCompletionsPath?: string;
   /**
-   * Endpoints this entry used to live at, kept so a saved custom provider that still points
+   * Canonical or historical endpoints, kept so a saved custom provider that still points
    * at one keeps receiving this row's metadata through `registryEntryForProviderDestination`.
    * Destination matching is by adapter plus normalized base URL, so moving a row's wire or
    * prefix would otherwise orphan every config a user wrote against the old address.

src/providers/service-tier.ts

@@ -33,6 +33,7 @@ type ServiceTierCapabilityProvider = Pick<
   | "modelAdapters"
   | "baseUrl"
   | "authMode"
+  | "googleMode"
   | "apiKeyTransport"
   | "chatServiceTier"
   | "fastWire"
@@ -119,7 +120,7 @@ function buildFastPolicyAuthority(
           : {}),
     }),
     modelAdapters: Object.freeze({ ...(provider.modelAdapters ?? {}) }),
-    hardPins: captureWireAdapterHardPins(providerName),
+    hardPins: captureWireAdapterHardPins(providerName, provider),
     hardPinPrefixes: captureWireAdapterHardPinPrefixes(providerName, provider),
     registryWireDefaults: cloneRegistryWireDefaults(registry?.modelWireDefaults),
   });

src/types/opencode-go.ts

@@ -0,0 +1,61 @@
+/** Exact-model protocols from https://opencode.ai/v2/docs/console/go/#endpoints (2026-10-15).
+ * Unknown models retain Chat. Responses entries are overridable registry defaults;
+ * the native wires are hard pins because modelAdapters cannot select those adapters.
+ */
+export const OPENCODE_GO_BASE_URL = "https://opencode.ai/zen/go/v1";
+
+export const OPENCODE_GO_MODEL_WIRES: Readonly<Record<string, "google" | "anthropic" | "openai-responses">> = Object.freeze({
+  "gemini-4-argon-contributor": "google",
+  "claude-haiku-5-5": "anthropic",
+  "minimax-m2.7": "anthropic",
+  "minimax-m3": "anthropic",
+  "qwen3.7-plus": "anthropic",
+  "qwen3.8-max": "anthropic",
+  "qwen3.8-flash": "anthropic",
+  "gpt-6-luna": "openai-responses",
+  "gpt-5.6-luna": "openai-responses",
+  "grok-4.6": "openai-responses",
+  "grok-4.7": "openai-responses",
+  "muse-spark-1.2-contributor": "openai-responses",
+  "muse-spark-1.3-contributor": "openai-responses",
+  // Retain previously supported Go models absent from the current endpoint table (#4847).
+  "minimax-m2.5": "anthropic",
+  "union-alpha": "anthropic",
+});
+
+/** Compatibility: these five pins predate destination scoping. New native pins require Go. */
+export const OPENCODE_GO_LEGACY_NAME_PINS: ReadonlySet<string> = new Set([
+  "claude-haiku-5-5", "minimax-m2.5", "minimax-m2.7", "minimax-m3", "union-alpha",
+]);
+
+export const OPENCODE_GO_RESPONSES_DEFAULTS = Object.freeze(Object.fromEntries(
+  Object.entries(OPENCODE_GO_MODEL_WIRES).filter(([, wire]) => wire === "openai-responses"),
+));
+
+export interface OpenCodeGoDestination {
+  readonly baseUrl?: unknown;
+  readonly authMode?: unknown;
+  readonly googleMode?: unknown;
+}
+
+/** A provider name alone must never authorize redirecting a credential to OpenCode. */
+export function isOpenCodeGoGeminiDestination(provider: OpenCodeGoDestination | undefined): boolean {
+  if (!provider || typeof provider.baseUrl !== "string") return false;
+  if (provider.authMode !== undefined && provider.authMode !== "key") return false;
+  if (provider.googleMode !== undefined && provider.googleMode !== "ai-studio") return false;
+  try {
+    const url = new URL(provider.baseUrl.trim());
+    return url.origin === "https://opencode.ai"
+      && !url.username && !url.password && !url.search && !url.hash
+      && ["/zen/go/v1", "/inference/go/v1"].includes(url.pathname.replace(/\/+$/, ""));
+  } catch {
+    return false;
+  }
+}
+
+/** Return the fixed Gemini endpoint only for the exact model and an eligible Go destination. */
+export function openCodeGoGeminiEndpoint(provider: OpenCodeGoDestination, modelId: string): string | undefined {
+  return Object.hasOwn(OPENCODE_GO_MODEL_WIRES, modelId) && OPENCODE_GO_MODEL_WIRES[modelId] === "google" && isOpenCodeGoGeminiDestination(provider)
+    ? `https://opencode.ai/inference/go/v1/models/${encodeURIComponent(modelId)}`
+    : undefined;
+}

src/types/wire.ts

@@ -1,3 +1,5 @@
+import { isOpenCodeGoGeminiDestination, OPENCODE_GO_BASE_URL, OPENCODE_GO_MODEL_WIRES, OPENCODE_GO_LEGACY_NAME_PINS, type OpenCodeGoDestination } from "./opencode-go";
+
 /**
  * Accepted values for the per-provider upstream HTTP-version pin (#1668). Shared by the
  * zod load schema, the management write boundary (POST/PATCH), and the fetch runtime, so
@@ -40,35 +42,16 @@ export const MODEL_ADAPTER_OVERRIDE_ALLOWED: ReadonlySet<string> = new Set([
   "openai-responses",
 ]);
 
-/**
- * Providers whose listed model ids must be driven over the Anthropic wire even when
- * the provider's configured adapter says otherwise — the upstream only speaks
- * Anthropic for these models.
- */
-const ANTHROPIC_WIRE_MODELS: Record<string, ReadonlySet<string>> = {
-  "opencode-go": new Set([
-    "claude-haiku-5-5",
-    "minimax-m2.5",
-    "minimax-m2.7",
-    "minimax-m3",
-    // OpenCode's catalog identifies Union Alpha as @ai-sdk/anthropic while the
-    // provider defaults to OpenAI-compatible; direct Chat returns 500 and direct
-    // Messages reaches the session check (#4847).
-    "union-alpha",
-  ]),
-};
-
-function anthropicWireModelsForProvider(providerName: string): ReadonlySet<string> | undefined {
-  return Object.hasOwn(ANTHROPIC_WIRE_MODELS, providerName)
-    ? ANTHROPIC_WIRE_MODELS[providerName]
-    : undefined;
-}
-
-/** Detached provider-local hard-pin table for pure wire-policy resolution. */
-export function captureWireAdapterHardPins(providerName: string): Readonly<Record<string, string>> {
-  const models = anthropicWireModelsForProvider(providerName);
-  if (!models) return Object.freeze({});
-  return Object.freeze(Object.fromEntries([...models].map(modelId => [modelId, "anthropic"])));
+/** Native Go wire pins share the exact-model table with registry Responses defaults. */
+export function captureWireAdapterHardPins(providerName: string, provider?: WirePinProvider): Readonly<Record<string, string>> {
+  if (providerName !== "opencode-go") return Object.freeze({});
+  // The existing Go preset pins saved URLs to this endpoint before dispatch. Pure policy
+  // captures must use that same destination even when handed an unnormalized config row.
+  const destination = provider && { ...provider, baseUrl: OPENCODE_GO_BASE_URL };
+  return Object.freeze(Object.fromEntries(Object.entries(OPENCODE_GO_MODEL_WIRES).filter(([modelId, wire]) =>
+    (wire === "anthropic" && OPENCODE_GO_LEGACY_NAME_PINS.has(modelId))
+    || (wire !== "openai-responses" && isOpenCodeGoGeminiDestination(destination)),
+  )));
 }
 
 interface WirePinPrefixRule {
@@ -98,9 +81,7 @@ const WIRE_ADAPTER_PIN_PREFIXES: Readonly<Record<string, WirePinPrefixRule>> = O
 });
 
 /** Just enough of a provider config to tell whether it still points at the pinned endpoint. */
-export interface WirePinProvider {
-  readonly baseUrl?: unknown;
-}
+export interface WirePinProvider extends OpenCodeGoDestination {}
 
 function normalizedEndpoint(value: unknown): string | undefined {
   if (typeof value !== "string") return undefined;
@@ -148,13 +129,11 @@ function prefixedWireAdapter(providerName: string, modelId: string, provider: Wi
  * adapter" would pass on the first pass and then let the override win on the second.
  */
 export function isWirePinnedModel(providerName: string, modelId: string, provider?: WirePinProvider): boolean {
-  return (anthropicWireModelsForProvider(providerName)?.has(modelId) ?? false)
-    || prefixedWireAdapter(providerName, modelId, provider) !== undefined;
+  return pinnedWireAdapter(providerName, modelId, provider) !== undefined;
 }
 
 /** The wire a pinned model must use, or undefined when the model is not pinned. */
 export function pinnedWireAdapter(providerName: string, modelId: string, provider?: WirePinProvider): string | undefined {
-  return anthropicWireModelsForProvider(providerName)?.has(modelId)
-    ? "anthropic"
-    : prefixedWireAdapter(providerName, modelId, provider);
+  const pins = captureWireAdapterHardPins(providerName, provider);
+  return Object.hasOwn(pins, modelId) ? pins[modelId] : prefixedWireAdapter(providerName, modelId, provider);
 }

structure/catalog.md

@@ -226,7 +226,7 @@ A Devin live row spreads its measured `inputModalities` before
 value survives only when none of them applies. Devin live rows collapse by catalog family (so `swe-1-6-fast` stays its own row), read their ladder from the family effort axis (including `minimal`), and carry the effective enabled default member's effort as `defaultReasoningEffort` when the family marks a default; `swe-1-6` is marked text-only because it drops images without an error.
 
 For `liveModels: false`, a static provider publishes the ordered union of `models` and `retainModels`. When `models` is absent or empty, its configured `defaultModel` seeds that
-union before retained ids; a nonempty explicit list does not import a different default.
+union before retained ids; a nonempty explicit list does not import a different default. The existing `opencode-go` preset retains name-based registry ownership: saved custom URLs are pinned to its canonical endpoint at routing, and omitted/empty models inherit its default unless explicitly overridden (`tests/codex-integration/catalog-opencode-go-static.test.ts`).
 Kiro keeps this static union as its floor and merges cached account model IDs and input limits; gathering neither refreshes tokens nor calls management, and runtime `/models` discovery remains disabled.
 Without any default or configured/retained ids, the static result stays empty. The existing
 forward-auth native path remains separate. Static gathering does not refresh OAuth or call