fix: map OpenCode Zen models to correct APIs

CHANGELOG.md

@@ -16,6 +16,7 @@ Docs: https://docs.clawd.bot
 ### Fixes
 - Config: avoid stack traces for invalid configs and log the config path.
 - Doctor: warn when gateway.mode is unset with configure/config guidance.
+- OpenCode Zen: route models to the Zen API shape per family so proxy endpoints are used. (#1416)
 - macOS: include Textual syntax highlighting resources in packaged app to prevent chat crashes. (#1362)
 - Cron: cap reminder context history to 10 messages and honor `contextMessages`. (#1103) Thanks @mkbehr.
 - Exec approvals: treat main as the default agent + migrate legacy default allowlists. (#1417) Thanks @czekaj.

src/agents/opencode-zen-models.test.ts

@@ -44,6 +44,8 @@ describe("resolveOpencodeZenModelApi", () => {
     expect(resolveOpencodeZenModelApi("minimax-m2.1-free")).toBe("anthropic-messages");
     expect(resolveOpencodeZenModelApi("gemini-3-pro")).toBe("google-generative-ai");
     expect(resolveOpencodeZenModelApi("gpt-5.2")).toBe("openai-responses");
+    expect(resolveOpencodeZenModelApi("alpha-gd4")).toBe("openai-completions");
+    expect(resolveOpencodeZenModelApi("big-pickle")).toBe("openai-completions");
     expect(resolveOpencodeZenModelApi("glm-4.7-free")).toBe("openai-completions");
     expect(resolveOpencodeZenModelApi("some-unknown-model")).toBe("openai-completions");
   });

src/agents/opencode-zen-models.ts

@@ -87,19 +87,19 @@ export function resolveOpencodeZenAlias(modelIdOrAlias: string): string {
 }
 
 /**
- * OpenCode Zen routes models to different APIs based on model family.
+ * OpenCode Zen routes models to specific API shapes by family.
  */
 export function resolveOpencodeZenModelApi(modelId: string): ModelApi {
   const lower = modelId.toLowerCase();
-  if (lower.startsWith("claude-") || lower.startsWith("minimax") || lower.startsWith("alpha-gd4")) {
+  if (lower.startsWith("gpt-")) {
+    return "openai-responses";
+  }
+  if (lower.startsWith("claude-") || lower.startsWith("minimax-")) {
     return "anthropic-messages";
   }
   if (lower.startsWith("gemini-")) {
     return "google-generative-ai";
   }
-  if (lower.startsWith("gpt-")) {
-    return "openai-responses";
-  }
   return "openai-completions";
 }