Add OpenCode Zen model discovery and protocol routing

packages/first-class-providers/src/providers.ts

@@ -5,6 +5,14 @@ import {
   OPENCODE_GO_MODEL_IDS,
   OPENCODE_GO_PROVIDER_ID,
 } from "../../opencode-go/src/index.js";
+import {
+  ZEN_AUTH_HINT,
+  ZEN_DEFAULT_BASE_URL,
+  ZEN_DEFAULT_MODEL,
+  ZEN_DISPLAY_NAME,
+  ZEN_MODEL_IDS,
+  ZEN_PROVIDER_ID,
+} from "../../zen/src/index.js";
 import type { FirstClassProviderDef } from "./types.js";
 
 const OPENAI_API_MODELS = [
@@ -85,23 +93,15 @@ export const FIRST_CLASS_PROVIDERS: readonly FirstClassProviderDef[] = [
     billingProduct: "subscription",
   },
   {
-    id: "zen",
-    label: "OpenCode Zen",
+    id: ZEN_PROVIDER_ID,
+    label: ZEN_DISPLAY_NAME,
     auth: "api-key",
-    baseURL: "https://opencode.ai/zen/v1",
-    models: [
-      "gpt-6-astra",
-      "gpt-5.4",
-      "gpt-5.4-mini",
-      "claude-fable-5-1",
-      "claude-sonnet-4-5",
-      "claude-opus-4-5",
-      "gemini-3-flash",
-      "gemini-3-pro",
-    ],
-    defaultModel: "claude-sonnet-4-5",
-    authHint:
-      "OpenCode Zen pay-as-you-go credits — paste your API key from https://opencode.ai/auth",
+    baseURL: ZEN_DEFAULT_BASE_URL,
+    // Static fallback seed: the Zen /models catalog is discovered live and
+    // overlaid at runtime; this list only covers discovery being unavailable.
+    models: ZEN_MODEL_IDS,
+    defaultModel: ZEN_DEFAULT_MODEL,
+    authHint: ZEN_AUTH_HINT,
     billingProduct: "credits",
   },
   {

packages/zen/package.json

@@ -0,0 +1,13 @@
+{
+  "name": "@corbits/provider-zen",
+  "version": "0.1.0",
+  "private": true,
+  "type": "module",
+  "license": "SEE LICENSE IN LICENSE.md",
+  "exports": {
+    ".": {
+      "types": "./src/index.ts",
+      "default": "./src/index.ts"
+    }
+  }
+}

packages/zen/src/constants.ts

@@ -0,0 +1,19 @@
+// OpenCode Zen pay-as-you-go endpoints.
+// Docs: https://opencode.ai/docs/zen/
+// Auth: API key from https://opencode.ai/auth topped up with Zen credits.
+
+export const ZEN_PROVIDER_ID = "zen";
+export const ZEN_DISPLAY_NAME = "OpenCode Zen";
+
+// OpenAI-compatible surface (chat completions + responses). Paths are relative
+// to this base: /chat/completions, /responses, /models.
+export const ZEN_DEFAULT_BASE_URL = "https://opencode.ai/zen/v1";
+
+// Anthropic Messages adapter appends `/v1/messages`, so the root (without /v1)
+// is the correct base for message-protocol models.
+export const ZEN_BASE_URL = "https://opencode.ai/zen";
+
+export const ZEN_MODELS_PATH = "/models";
+
+export const ZEN_AUTH_HINT =
+  "OpenCode Zen pay-as-you-go credits — paste your API key from https://opencode.ai/auth";

packages/zen/src/endpoint.ts

@@ -0,0 +1,34 @@
+// Resolve the Zen endpoint + provider adapter from the protocol map.
+// Mirrors the OpenCode Go endpoint module; Go paths are untouched.
+
+import { ZEN_BASE_URL, ZEN_DEFAULT_BASE_URL } from "./constants.js";
+import { protocolForZenModel, type ZenProtocol } from "./models.js";
+
+export type ZenEndpointKind =
+  | "anthropic"
+  | "openai-compatible"
+  | "openai-responses";
+
+export interface ZenEndpoint {
+  baseURL: string;
+  adapter: ZenEndpointKind;
+}
+
+const ENDPOINT_BY_PROTOCOL: Record<ZenProtocol, ZenEndpoint> = {
+  messages: { baseURL: ZEN_BASE_URL, adapter: "anthropic" },
+  responses: { baseURL: ZEN_DEFAULT_BASE_URL, adapter: "openai-responses" },
+  "chat-completions": {
+    baseURL: ZEN_DEFAULT_BASE_URL,
+    adapter: "openai-compatible",
+  },
+};
+
+/** Map hit if and only if this model pins Zen protocol selection. */
+export function zenProtocolForModel(model: string): ZenProtocol {
+  return protocolForZenModel(model);
+}
+
+/** Route a Zen model to its endpoint. Unknown ids stay on chat completions. */
+export function resolveZenEndpoint(model: string): ZenEndpoint {
+  return ENDPOINT_BY_PROTOCOL[zenProtocolForModel(model)];
+}

packages/zen/src/identity.ts

@@ -0,0 +1,48 @@
+// Zen provider identity: detect a Zen-configured provider from an explicit
+// provider id or a bare Zen base URL. Mirrors the OpenCode Go identity
+// helpers; Go's own URL and id keep matching Go first, never Zen.
+
+import { ZEN_DISPLAY_NAME, ZEN_PROVIDER_ID } from "./constants.js";
+
+function hostMatchesOpencodeDotAi(host: string): boolean {
+  const normalized = host.trim().toLowerCase();
+  return normalized === "opencode.ai" || normalized.endsWith(".opencode.ai");
+}
+
+/**
+ * Match a bare Zen base URL: an opencode.ai URL whose first path segment is
+ * "zen". The Go catalog URL (https://opencode.ai/zen/go/...) matches Go,
+ * never Zen — callers must check Go first.
+ */
+export function isZenURL(value: string | undefined): boolean {
+  if (!value) return false;
+  try {
+    const url = new URL(value);
+    if (!hostMatchesOpencodeDotAi(url.hostname)) return false;
+    const segments = url.pathname.split("/").filter((part) => part !== "");
+    return (
+      segments[0]?.toLowerCase() === "zen" &&
+      segments[1]?.toLowerCase() !== "go"
+    );
+  } catch {
+    return false;
+  }
+}
+
+/** Match the Zen provider id or display name (case-insensitive). */
+export function isZenProviderId(value: string | undefined): boolean {
+  if (!value) return false;
+  const normalized = value.trim().toLowerCase();
+  return (
+    normalized === ZEN_PROVIDER_ID ||
+    normalized === ZEN_DISPLAY_NAME.toLowerCase()
+  );
+}
+
+/** Match either an explicit Zen provider id or a bare Zen base URL. */
+export function isZenProvider(ref: {
+  name?: string;
+  baseURL?: string;
+}): boolean {
+  return isZenProviderId(ref.name) || isZenURL(ref.baseURL);
+}

packages/zen/src/index.ts

@@ -0,0 +1,22 @@
+export {
+  ZEN_AUTH_HINT,
+  ZEN_BASE_URL,
+  ZEN_DEFAULT_BASE_URL,
+  ZEN_DISPLAY_NAME,
+  ZEN_MODELS_PATH,
+  ZEN_PROVIDER_ID,
+} from "./constants.js";
+export {
+  resolveZenEndpoint,
+  zenProtocolForModel,
+  type ZenEndpoint,
+  type ZenEndpointKind,
+} from "./endpoint.js";
+export { isZenProvider, isZenProviderId, isZenURL } from "./identity.js";
+export {
+  isKnownZenModel,
+  protocolForZenModel,
+  ZEN_DEFAULT_MODEL,
+  ZEN_MODEL_IDS,
+  type ZenProtocol,
+} from "./models.js";

packages/zen/src/models.ts

@@ -0,0 +1,112 @@
+// Known OpenCode Zen models and the wire protocol each one requires, from
+// https://opencode.ai/docs/zen/#available-models. Zen's /models catalog is
+// the live source of truth; this map only pins the protocol assignment per
+// known id. Unknown ids default to chat completions (the status quo).
+
+/** Packaged fallback seed: live discovery fallback + picker default, never empty. */
+export const ZEN_MODEL_IDS: readonly string[] = [
+  "gpt-6-astra",
+  "gpt-5.4",
+  "gpt-5.4-mini",
+  "claude-fable-5-1",
+  "claude-sonnet-4-5",
+  "claude-opus-4-5",
+  "gemini-3-flash",
+  "gemini-3-pro",
+];
+
+export const ZEN_DEFAULT_MODEL = "claude-sonnet-4-5";
+
+export type ZenProtocol = "messages" | "responses" | "chat-completions";
+
+interface ZenModel {
+  id: string;
+  protocol: ZenProtocol;
+}
+
+const ZEN_MODELS: readonly ZenModel[] = [
+  // Anthropic Messages API
+  { id: "claude-fable-5-1", protocol: "messages" },
+  { id: "claude-fable-5", protocol: "messages" },
+  { id: "claude-opus-5", protocol: "messages" },
+  { id: "claude-opus-4-8", protocol: "messages" },
+  { id: "claude-opus-4-7", protocol: "messages" },
+  { id: "claude-opus-4-6", protocol: "messages" },
+  { id: "claude-opus-4-5", protocol: "messages" },
+  { id: "claude-sonnet-5", protocol: "messages" },
+  { id: "claude-sonnet-4-6", protocol: "messages" },
+  { id: "claude-sonnet-4-5", protocol: "messages" },
+  { id: "claude-haiku-4-5", protocol: "messages" },
+  { id: "qwen3.7-max", protocol: "messages" },
+  { id: "qwen3.7-plus", protocol: "messages" },
+  { id: "qwen3.6-plus", protocol: "messages" },
+  { id: "qwen3.5-plus", protocol: "messages" },
+  // OpenAI Responses API
+  { id: "gpt-6-astra", protocol: "responses" },
+  { id: "gpt-5.6-sol", protocol: "responses" },
+  { id: "gpt-5.6-terra", protocol: "responses" },
+  { id: "gpt-5.6-luna", protocol: "responses" },
+  { id: "gpt-5.5", protocol: "responses" },
+  { id: "gpt-5.5-pro", protocol: "responses" },
+  { id: "gpt-5.4", protocol: "responses" },
+  { id: "gpt-5.4-pro", protocol: "responses" },
+  { id: "gpt-5.4-mini", protocol: "responses" },
+  { id: "gpt-5.4-nano", protocol: "responses" },
+  { id: "gpt-5.3-codex", protocol: "responses" },
+  { id: "gpt-5.3-codex-spark", protocol: "responses" },
+  { id: "gpt-5.2", protocol: "responses" },
+  { id: "gpt-5.2-codex", protocol: "responses" },
+  { id: "gpt-5.1", protocol: "responses" },
+  { id: "gpt-5.1-codex", protocol: "responses" },
+  { id: "gpt-5.1-codex-max", protocol: "responses" },
+  { id: "gpt-5.1-codex-mini", protocol: "responses" },
+  { id: "gpt-5", protocol: "responses" },
+  { id: "gpt-5-codex", protocol: "responses" },
+  { id: "gpt-5-nano", protocol: "responses" },
+  { id: "grok-4.6", protocol: "responses" },
+  { id: "grok-4.5", protocol: "responses" },
+  { id: "grok-build-0.1", protocol: "responses" },
+  { id: "muse-spark-1.3", protocol: "responses" },
+  { id: "muse-spark-1.2", protocol: "responses" },
+  { id: "muse-spark-1.3-contributor-free", protocol: "responses" },
+  // OpenAI Chat Completions API (explicit; unknown ids also land here)
+  { id: "deepseek-v4-pro", protocol: "chat-completions" },
+  { id: "deepseek-v4-flash", protocol: "chat-completions" },
+  { id: "deepseek-v4-flash-vision-exp", protocol: "chat-completions" },
+  { id: "minimax-m3", protocol: "chat-completions" },
+  { id: "minimax-m2.7", protocol: "chat-completions" },
+  { id: "minimax-m2.5", protocol: "chat-completions" },
+  { id: "glm-5.3-flash", protocol: "chat-completions" },
+  { id: "glm-5.3", protocol: "chat-completions" },
+  { id: "glm-5.2", protocol: "chat-completions" },
+  { id: "glm-5.1", protocol: "chat-completions" },
+  { id: "glm-5", protocol: "chat-completions" },
+  { id: "kimi-k2.5", protocol: "chat-completions" },
+  { id: "kimi-k2.6", protocol: "chat-completions" },
+  { id: "kimi-k2.7-code", protocol: "chat-completions" },
+  { id: "kimi-k3", protocol: "chat-completions" },
+  { id: "big-pickle", protocol: "chat-completions" },
+  { id: "mimo-v2.5-free", protocol: "chat-completions" },
+  { id: "ling-3.0-flash-fin-free", protocol: "chat-completions" },
+  { id: "nemotron-3-ultra-free", protocol: "chat-completions" },
+  { id: "nemotron-3.5-lightning-free", protocol: "chat-completions" },
+  { id: "gemini-3-flash", protocol: "chat-completions" },
+  { id: "gemini-3-pro", protocol: "chat-completions" },
+];
+
+const PROTOCOL_BY_ID = new Map<string, ZenProtocol>(
+  ZEN_MODELS.map((model) => [model.id, model.protocol]),
+);
+
+/**
+ * Return the wire protocol for a known Zen model id. Unknown ids default to
+ * chat completions — the status quo for an unmapped model, never inferred
+ * from name prefixes.
+ */
+export function protocolForZenModel(modelId: string): ZenProtocol {
+  return PROTOCOL_BY_ID.get(modelId) ?? "chat-completions";
+}
+
+export function isKnownZenModel(modelId: string): boolean {
+  return PROTOCOL_BY_ID.has(modelId);
+}