fix: address PR review feedback

- Add unit tests for copilotHome option in all 4 SDKs
- Fix Python README: add missing 'Ignored when using ExternalServerConfig' caveat
- Fix Go README: clarify that CopilotHome option controls CLI subprocess env,
  not embedded binary cache (use COPILOT_HOME env var or embeddedcli.Config.Dir
  for that)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: patniko

dotnet/test/Unit/CloneTests.cs

@@ -26,6 +26,7 @@ public void CopilotClientOptions_Clone_CopiesAllProperties()
             Environment = new Dictionary<string, string> { ["KEY"] = "value" },
             GitHubToken = "ghp_test",
             UseLoggedInUser = false,
+            CopilotHome = "/custom/copilot/home",
             SessionIdleTimeoutSeconds = 600,
         };
 
@@ -43,6 +44,7 @@ public void CopilotClientOptions_Clone_CopiesAllProperties()
         Assert.Equal(original.Environment, clone.Environment);
         Assert.Equal(original.GitHubToken, clone.GitHubToken);
         Assert.Equal(original.UseLoggedInUser, clone.UseLoggedInUser);
+        Assert.Equal(original.CopilotHome, clone.CopilotHome);
         Assert.Equal(original.SessionIdleTimeoutSeconds, clone.SessionIdleTimeoutSeconds);
     }
 

go/README.md

@@ -133,7 +133,7 @@ Event types: `SessionLifecycleCreated`, `SessionLifecycleDeleted`, `SessionLifec
 - `CLIPath` (string): Path to CLI executable (default: "copilot" or `COPILOT_CLI_PATH` env var)
 - `CLIUrl` (string): URL of existing CLI server (e.g., `"localhost:8080"`, `"http://127.0.0.1:9000"`, or just `"8080"`). When provided, the client will not spawn a CLI process.
 - `Cwd` (string): Working directory for CLI process
-- `CopilotHome` (string): Base directory for Copilot data (session state, config, etc.). Sets `COPILOT_HOME` on the spawned CLI process. When empty, the CLI defaults to `~/.copilot`. Also used as the default cache directory for the embedded CLI binary. Useful in restricted environments where only specific directories are writable. Ignored when using `CLIUrl`.
+- `CopilotHome` (string): Base directory for Copilot data (session state, config, etc.). Sets `COPILOT_HOME` on the spawned CLI process. When empty, the CLI defaults to `~/.copilot`. Useful in restricted environments where only specific directories are writable. Ignored when using `CLIUrl`. To also control where the embedded CLI binary is cached, set the `COPILOT_HOME` environment variable in the parent process or use `embeddedcli.Config.Dir`.
 - `Port` (int): Server port for TCP mode (default: 0 for random)
 - `UseStdio` (bool): Use stdio transport instead of TCP (default: true)
 - `LogLevel` (string): Log level (default: "info")

go/client_test.go

@@ -344,6 +344,26 @@ func TestClient_AuthOptions(t *testing.T) {
 	})
 }
 
+func TestClient_CopilotHome(t *testing.T) {
+	t.Run("should accept CopilotHome option", func(t *testing.T) {
+		client := NewClient(&ClientOptions{
+			CopilotHome: "/custom/copilot/home",
+		})
+
+		if client.options.CopilotHome != "/custom/copilot/home" {
+			t.Errorf("Expected CopilotHome to be '/custom/copilot/home', got %q", client.options.CopilotHome)
+		}
+	})
+
+	t.Run("should default CopilotHome to empty string", func(t *testing.T) {
+		client := NewClient(&ClientOptions{})
+
+		if client.options.CopilotHome != "" {
+			t.Errorf("Expected CopilotHome to be empty, got %q", client.options.CopilotHome)
+		}
+	})
+}
+
 func TestClient_EnvOptions(t *testing.T) {
 	t.Run("should store custom environment variables", func(t *testing.T) {
 		client := NewClient(&ClientOptions{

nodejs/test/client.test.ts

@@ -662,6 +662,23 @@ describe("CopilotClient", () => {
             expect((client as any).options.useLoggedInUser).toBe(false);
         });
 
+        it("should accept copilotHome option", () => {
+            const client = new CopilotClient({
+                copilotHome: "/custom/copilot/home",
+                logLevel: "error",
+            });
+
+            expect((client as any).options.copilotHome).toBe("/custom/copilot/home");
+        });
+
+        it("should leave copilotHome undefined when not provided", () => {
+            const client = new CopilotClient({
+                logLevel: "error",
+            });
+
+            expect((client as any).options.copilotHome).toBeUndefined();
+        });
+
         it("should throw error when gitHubToken is used with cliUrl", () => {
             expect(() => {
                 new CopilotClient({

python/README.md

@@ -153,7 +153,7 @@ CopilotClient(
 - `log_level` (str): Log level (default: "info")
 - `env` (dict | None): Environment variables for the CLI process
 - `github_token` (str | None): GitHub token for authentication. When provided, takes priority over other auth methods.
-- `copilot_home` (str | None): Base directory for Copilot data (session state, config, etc.). Sets `COPILOT_HOME` on the spawned CLI process. When `None`, the CLI defaults to `~/.copilot`. Useful in restricted environments where only specific directories are writable.
+- `copilot_home` (str | None): Base directory for Copilot data (session state, config, etc.). Sets `COPILOT_HOME` on the spawned CLI process. When `None`, the CLI defaults to `~/.copilot`. Useful in restricted environments where only specific directories are writable. Ignored when using `ExternalServerConfig`.
 - `use_logged_in_user` (bool | None): Whether to use logged-in user for authentication (default: True, but False when `github_token` is provided).
 - `telemetry` (dict | None): OpenTelemetry configuration for the CLI process. Providing this enables telemetry — no separate flag needed. See [Telemetry](#telemetry) below.
 

python/test_client.py

@@ -222,6 +222,29 @@ def test_default_session_idle_timeout_seconds_is_none(self):
         assert client._config.session_idle_timeout_seconds is None
 
 
+class TestCopilotHome:
+    def test_accepts_copilot_home(self):
+        client = CopilotClient(
+            SubprocessConfig(
+                cli_path=CLI_PATH,
+                copilot_home="/custom/copilot/home",
+                log_level="error",
+            )
+        )
+        assert isinstance(client._config, SubprocessConfig)
+        assert client._config.copilot_home == "/custom/copilot/home"
+
+    def test_default_copilot_home_is_none(self):
+        client = CopilotClient(
+            SubprocessConfig(
+                cli_path=CLI_PATH,
+                log_level="error",
+            )
+        )
+        assert isinstance(client._config, SubprocessConfig)
+        assert client._config.copilot_home is None
+
+
 class TestOverridesBuiltInTool:
     @pytest.mark.asyncio
     async def test_overrides_built_in_tool_sent_in_tool_definition(self):