Accept the hosted workspace alias as Claude stdio cwd

apps/daemon/internal/agent/claudesdk/mcp_environment.go

@@ -20,8 +20,7 @@ type environmentMCPServer struct {
 	Declared bool `json:"declared,omitempty"`
 }
 
-// cwd is the directory the native process starts in; native starts stdio servers there.
-func prepareRuntimeMCP(req proto.PromptRequestPayload, cwd string) ([]environmentMCPServer, []string, error) {
+func prepareRuntimeMCP(req proto.PromptRequestPayload) ([]environmentMCPServer, []string, error) {
 	bindings, err := agent.ResolveMCPBindings(req)
 	if err != nil {
 		return nil, nil, err
@@ -33,7 +32,9 @@ func prepareRuntimeMCP(req proto.PromptRequestPayload, cwd string) ([]environmen
 			return nil, nil, fmt.Errorf("claudesdk: unsupported MCP identity")
 		}
 		if process := binding.Process; process != nil {
-			if filepath.Clean(process.Cwd) != cwd {
+			// Native starts stdio servers in its workspace, which the declared
+			// directory names directly or through the hosted /workspace alias.
+			if req.LocalEnvironment == nil || filepath.Clean(process.Cwd) != req.LocalEnvironment.WorkspaceDirectory {
 				return nil, nil, fmt.Errorf("claudesdk: MCP stdio cwd must be the workspace directory")
 			}
 			args := append([]string{}, process.Args...)

apps/daemon/internal/agent/claudesdk/mcp_environment_test.go

@@ -65,7 +65,7 @@ func TestEnvironmentMCPRejectsUnqualifiedCombinations(t *testing.T) {
 	} {
 		environment := &proto.LocalEnvironment{MCP: []proto.EnvironmentMCP{{InstallationRoot: "/private/runtime/capabilities", WorkspaceRoot: "/private/runtime/workspace", PackageRoot: "plugins/remote", Server: agentplugin.MCPServer{Name: "remote", Type: "http", URL: "https://example.invalid/mcp"}}}}
 		mutate(environment)
-		if _, _, err := prepareRuntimeMCP(proto.PromptRequestPayload{LocalEnvironment: environment}, ""); err == nil {
+		if _, _, err := prepareRuntimeMCP(proto.PromptRequestPayload{LocalEnvironment: environment}); err == nil {
 			t.Fatal("unsupported declaration accepted")
 		}
 	}
@@ -91,17 +91,18 @@ func TestEnvironmentMCPObservationsUseInstalledDeclarations(t *testing.T) {
 }
 
 // Native starts a stdio server in the directory of its own process, so the
-// declared cwd must be that workspace directory.
+// declared cwd must be the declared workspace directory.
 func TestPublicMCPStdioStartsInTheWorkspaceDirectory(t *testing.T) {
 	servers := []proto.MCPHTTPServer{{ConnectionOrigin: "environment", ServerLabel: "local",
-		Stdio: &proto.MCPStdio{Command: "run", Cwd: "/work", EnvVars: []string{"TOKEN"}}}}
-	req := proto.PromptRequestPayload{LocalEnvironment: &proto.LocalEnvironment{}, MCPHTTPServers: &servers}
-	projected, _, err := prepareRuntimeMCP(req, "/work")
+		Stdio: &proto.MCPStdio{Command: "run", Cwd: "/workspace", EnvVars: []string{"TOKEN"}}}}
+	req := proto.PromptRequestPayload{LocalEnvironment: &proto.LocalEnvironment{WorkspaceDirectory: "/workspace", WorkspaceRoot: "/environment/workspace"}, MCPHTTPServers: &servers}
+	projected, _, err := prepareRuntimeMCP(req)
 	raw, _ := json.Marshal(projected)
 	if err != nil || string(raw) != `[{"server_label":"local","allowed_tools":null,"command":"run","args":[],"declared":true}]` {
 		t.Fatal("public stdio server was not projected", string(raw), err)
 	}
-	if _, _, err := prepareRuntimeMCP(req, "/elsewhere"); err == nil {
+	req.LocalEnvironment.WorkspaceDirectory = "/elsewhere"
+	if _, _, err := prepareRuntimeMCP(req); err == nil {
 		t.Fatal("stdio cwd outside the workspace directory was accepted")
 	}
 }

apps/daemon/internal/agent/claudesdk/options.go

@@ -164,7 +164,7 @@ func prepareConfiguration(config Config, req proto.PromptRequestPayload) (startR
 	}
 	env := withProvider(append(append([]string{}, os.Environ()...), config.Env...), provider)
 	env = append(env, "CLAUDE_CONFIG_DIR="+config.StateDir, "TMPDIR="+filepath.Join(config.StateDir, "tmp"))
-	projectedMCP, mcpEnv, err := prepareRuntimeMCP(req, "")
+	projectedMCP, mcpEnv, err := prepareRuntimeMCP(req)
 	if err != nil {
 		return startRequest{}, nil, err
 	}

apps/daemon/internal/agent/claudesdk/workspace.go

@@ -57,7 +57,7 @@ func prepareWorkspace(config Config, req proto.PromptRequestPayload) (*workspace
 		profile.Skills = req.LocalEnvironment.Skills
 		profile.CapabilityRoot = req.LocalEnvironment.CapabilityRoot
 	}
-	servers, credentials, err := prepareRuntimeMCP(req, workspaceCwd(config.Workspace))
+	servers, credentials, err := prepareRuntimeMCP(req)
 	if err != nil {
 		return nil, nil, err
 	}