fix(catalog): routed copilot mai-code models to responses api

GitHub Copilot's mai-code-1-flash-picker (and other mai-* models) are
served only through the /responses endpoint; the classifier routed them
to /chat/completions, which returned 400 unsupported_api_for_model.

Added the mai- prefix to isCopilotResponsesModelId so both dynamic
discovery (inferCopilotApi) and bundled resolution
(COPILOT_API_RESOLUTION_RULES) select openai-responses, and updated the
bundled models.json entry to match.

Fixes #5612

packages/catalog/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Fixed GitHub Copilot `mai-code-1-flash-picker` (and other `mai-*` models) to route through the `/responses` endpoint instead of `/chat/completions`, which rejected them with `400 unsupported_api_for_model` ([#5612](https://github.com/can1357/oh-my-pi/issues/5612)).
+
 ## [16.5.2] - 2026-07-14
 
 ### Fixed

packages/catalog/src/models.json

@@ -19406,7 +19406,7 @@
 		"mai-code-1-flash-picker": {
 			"id": "mai-code-1-flash-picker",
 			"name": "MAI-Code-1-Flash",
-			"api": "openai-completions",
+			"api": "openai-responses",
 			"provider": "github-copilot",
 			"baseUrl": "https://api.githubcopilot.com",
 			"reasoning": true,
@@ -19425,11 +19425,6 @@
 				"User-Agent": "opencode/1.3.15",
 				"X-GitHub-Api-Version": "2026-06-01"
 			},
-			"compat": {
-				"supportsStore": false,
-				"supportsDeveloperRole": false,
-				"supportsReasoningEffort": false
-			},
 			"thinking": {
 				"mode": "effort",
 				"efforts": [

packages/catalog/src/provider-models/openai-compat.ts

@@ -3724,7 +3724,7 @@ export interface GithubCopilotModelManagerConfig {
 
 const COPILOT_ANTHROPIC_MODEL_PATTERN = /^claude-(haiku|sonnet|opus|fable|mythos)-\d/;
 const isCopilotResponsesModelId = (modelId: string): boolean =>
-	modelId.startsWith("gpt-5") || modelId.startsWith("oswe");
+	modelId.startsWith("gpt-5") || modelId.startsWith("oswe") || modelId.startsWith("mai-");
 
 function inferCopilotApi(modelId: string): Api {
 	if (COPILOT_ANTHROPIC_MODEL_PATTERN.test(modelId)) {

packages/catalog/test/github-copilot-model-limits.test.ts

@@ -303,6 +303,22 @@ describe("github copilot model limits mapping", () => {
 		// not the OpenAI global reference (1050k).
 		expect(model?.contextWindow).toBe(272_000);
 	});
+	it("routes mai-code models to the openai-responses endpoint (#5612)", async () => {
+		// Copilot's /chat/completions rejects mai-* models with
+		// `unsupported_api_for_model` (400); they are served only via /responses.
+		const { models } = await discoverCopilotModels({
+			data: [
+				{
+					id: "mai-code-1-flash-picker",
+					name: "MAI-Code-1-Flash",
+				},
+			],
+		});
+
+		const model = models.find(candidate => candidate.id === "mai-code-1-flash-picker");
+		expect(model).toBeDefined();
+		expect(model?.api).toBe("openai-responses");
+	});
 });
 
 /**