diff --git a/packages/core/script/wellknown-server.ts b/packages/core/script/wellknown-server.ts
new file mode 100644
index 0000000000..f8a513059f
--- /dev/null
+++ b/packages/core/script/wellknown-server.ts
@@ -0,0 +1,112 @@
+const token = "dummy-wellknown-token"
+const port = Number(process.env.PORT ?? 8787)
+const config = {
+  $schema: "https://opencode.ai/config.json",
+  share: "manual",
+  model: "example-primary/example-chat",
+  enabled_providers: ["example-primary", "example-secondary"],
+  disabled_providers: ["opencode", "anthropic", "openai", "google", "xai", "amazon-bedrock", "azure"],
+  provider: {
+    "example-primary": {
+      name: "Example Primary",
+      npm: "@ai-sdk/openai-compatible",
+      whitelist: ["example-chat", "example-code"],
+      options: {
+        baseURL: "https://models.example.com/v1",
+        apiKey: "{env:TOKEN}",
+      },
+      models: {
+        "example-chat": {
+          name: "Example Chat",
+          reasoning: true,
+          tool_call: true,
+          attachment: true,
+          modalities: {
+            input: ["text", "image"],
+            output: ["text"],
+          },
+          limit: {
+            context: 128000,
+            output: 16000,
+          },
+        },
+        "example-code": {
+          name: "Example Code",
+          reasoning: true,
+          tool_call: true,
+          limit: {
+            context: 200000,
+            output: 32000,
+          },
+        },
+      },
+    },
+    "example-secondary": {
+      name: "Example Secondary",
+      npm: "@ai-sdk/openai-compatible",
+      whitelist: ["example-fast"],
+      options: {
+        baseURL: "https://inference.example.org/v1",
+        apiKey: "{env:TOKEN}",
+      },
+      models: {
+        "example-fast": {
+          name: "Example Fast",
+          tool_call: true,
+          limit: {
+            context: 64000,
+            output: 8000,
+          },
+        },
+      },
+    },
+  },
+  mcp: {
+    "example-tools": {
+      type: "remote",
+      url: "https://tools.example.net/mcp",
+      enabled: false,
+    },
+  },
+  permission: {
+    bash: "ask",
+    edit: "ask",
+    webfetch: "ask",
+    read: {
+      "*": "allow",
+      "*.env": "deny",
+      "*.env.*": "deny",
+      "*.env.example": "allow",
+    },
+  },
+}
+
+const server = Bun.serve({
+  hostname: "127.0.0.1",
+  port,
+  async fetch(request) {
+    const url = new URL(request.url)
+    if (url.pathname === "/.well-known/opencode") {
+      return Response.json({
+        auth: {
+          command: ["bun", "-e", `await Bun.sleep(5000); process.stdout.write(${JSON.stringify(token)})`],
+          env: "TOKEN",
+        },
+        remote_config: {
+          url: `${url.origin}/config/opencode.json`,
+          headers: { authorization: "Bearer {env:TOKEN}" },
+        },
+      })
+    }
+    if (url.pathname === "/config/opencode.json") {
+      if (request.headers.get("authorization") !== `Bearer ${token}`) {
+        return new Response("Unauthorized", { status: 401 })
+      }
+      return Response.json(config)
+    }
+    return new Response("Not found", { status: 404 })
+  },
+})
+
+console.log(`Well-known fixture listening at ${server.url.origin}`)
+console.log(`Test with: bun run dev auth connect ${server.url.origin}`)