Disable env-bound tools when exec server is none (#16349)

## Summary
- make `CODEX_EXEC_SERVER_URL=none` map to an explicit disabled
environment mode instead of inferring from a missing URL
- expose environment capabilities (`exec_enabled`, `filesystem_enabled`)
so tool building can gate behavior explicitly and future
multi-environment work has a clearer seam
- suppress env-backed tools when the relevant capability is unavailable,
including exec tools, `js_repl`, `apply_patch`, `list_dir`, and
`view_image`
- keep handler/runtime backstops so disabled environments still reject
execution if a tool path somehow bypasses registration

## Testing
- `just fmt`
- `cargo test -p codex-exec-server`
- `cargo test -p codex-tools
disabled_environment_omits_environment_backed_tools`
- `cargo test -p codex-tools
environment_capabilities_gate_exec_and_filesystem_tools_independently`
- remote devbox Bazel build via `codex-applied-devbox`:
`//codex-rs/cli:cli`

codex-rs/tools/src/tool_config.rs

@@ -86,6 +86,7 @@ pub struct ToolsConfig {
     pub shell_type: ConfigShellToolType,
     pub shell_command_backend: ShellCommandBackendConfig,
     pub unified_exec_shell_mode: UnifiedExecShellMode,
+    pub has_environment: bool,
     pub allow_login_shell: bool,
     pub apply_patch_tool_type: Option<ApplyPatchToolType>,
     pub web_search_mode: Option<WebSearchMode>,
@@ -200,6 +201,7 @@ impl ToolsConfig {
             shell_type,
             shell_command_backend,
             unified_exec_shell_mode: UnifiedExecShellMode::Direct,
+            has_environment: true,
             allow_login_shell: true,
             apply_patch_tool_type,
             web_search_mode: *web_search_mode,
@@ -236,6 +238,11 @@ impl ToolsConfig {
         self
     }
 
+    pub fn with_has_environment(mut self, has_environment: bool) -> Self {
+        self.has_environment = has_environment;
+        self
+    }
+
     pub fn with_unified_exec_shell_mode(
         mut self,
         unified_exec_shell_mode: UnifiedExecShellMode,

codex-rs/tools/src/tool_registry_plan.rs

@@ -107,54 +107,56 @@ pub fn build_tool_registry_plan(
         );
     }
 
-    match &config.shell_type {
-        ConfigShellToolType::Default => {
-            plan.push_spec(
-                create_shell_tool(ShellToolOptions {
-                    exec_permission_approvals_enabled,
-                }),
-                /*supports_parallel_tool_calls*/ true,
-                config.code_mode_enabled,
-            );
-        }
-        ConfigShellToolType::Local => {
-            plan.push_spec(
-                create_local_shell_tool(),
-                /*supports_parallel_tool_calls*/ true,
-                config.code_mode_enabled,
-            );
-        }
-        ConfigShellToolType::UnifiedExec => {
-            plan.push_spec(
-                create_exec_command_tool(CommandToolOptions {
-                    allow_login_shell: config.allow_login_shell,
-                    exec_permission_approvals_enabled,
-                }),
-                /*supports_parallel_tool_calls*/ true,
-                config.code_mode_enabled,
-            );
-            plan.push_spec(
-                create_write_stdin_tool(),
-                /*supports_parallel_tool_calls*/ false,
-                config.code_mode_enabled,
-            );
-            plan.register_handler("exec_command", ToolHandlerKind::UnifiedExec);
-            plan.register_handler("write_stdin", ToolHandlerKind::UnifiedExec);
-        }
-        ConfigShellToolType::Disabled => {}
-        ConfigShellToolType::ShellCommand => {
-            plan.push_spec(
-                create_shell_command_tool(CommandToolOptions {
-                    allow_login_shell: config.allow_login_shell,
-                    exec_permission_approvals_enabled,
-                }),
-                /*supports_parallel_tool_calls*/ true,
-                config.code_mode_enabled,
-            );
+    if config.has_environment {
+        match &config.shell_type {
+            ConfigShellToolType::Default => {
+                plan.push_spec(
+                    create_shell_tool(ShellToolOptions {
+                        exec_permission_approvals_enabled,
+                    }),
+                    /*supports_parallel_tool_calls*/ true,
+                    config.code_mode_enabled,
+                );
+            }
+            ConfigShellToolType::Local => {
+                plan.push_spec(
+                    create_local_shell_tool(),
+                    /*supports_parallel_tool_calls*/ true,
+                    config.code_mode_enabled,
+                );
+            }
+            ConfigShellToolType::UnifiedExec => {
+                plan.push_spec(
+                    create_exec_command_tool(CommandToolOptions {
+                        allow_login_shell: config.allow_login_shell,
+                        exec_permission_approvals_enabled,
+                    }),
+                    /*supports_parallel_tool_calls*/ true,
+                    config.code_mode_enabled,
+                );
+                plan.push_spec(
+                    create_write_stdin_tool(),
+                    /*supports_parallel_tool_calls*/ false,
+                    config.code_mode_enabled,
+                );
+                plan.register_handler("exec_command", ToolHandlerKind::UnifiedExec);
+                plan.register_handler("write_stdin", ToolHandlerKind::UnifiedExec);
+            }
+            ConfigShellToolType::Disabled => {}
+            ConfigShellToolType::ShellCommand => {
+                plan.push_spec(
+                    create_shell_command_tool(CommandToolOptions {
+                        allow_login_shell: config.allow_login_shell,
+                        exec_permission_approvals_enabled,
+                    }),
+                    /*supports_parallel_tool_calls*/ true,
+                    config.code_mode_enabled,
+                );
+            }
         }
     }
 
-    if config.shell_type != ConfigShellToolType::Disabled {
+    if config.has_environment && config.shell_type != ConfigShellToolType::Disabled {
         plan.register_handler("shell", ToolHandlerKind::Shell);
         plan.register_handler("container.exec", ToolHandlerKind::Shell);
         plan.register_handler("local_shell", ToolHandlerKind::Shell);
@@ -189,7 +191,7 @@ pub fn build_tool_registry_plan(
     );
     plan.register_handler("update_plan", ToolHandlerKind::Plan);
 
-    if config.js_repl_enabled {
+    if config.has_environment && config.js_repl_enabled {
         plan.push_spec(
             create_js_repl_tool(),
             /*supports_parallel_tool_calls*/ false,
@@ -265,7 +267,9 @@ pub fn build_tool_registry_plan(
         plan.register_handler(TOOL_SUGGEST_TOOL_NAME, ToolHandlerKind::ToolSuggest);
     }
 
-    if let Some(apply_patch_tool_type) = &config.apply_patch_tool_type {
+    if config.has_environment
+        && let Some(apply_patch_tool_type) = &config.apply_patch_tool_type
+    {
         match apply_patch_tool_type {
             ApplyPatchToolType::Freeform => {
                 plan.push_spec(
@@ -285,10 +289,11 @@ pub fn build_tool_registry_plan(
         plan.register_handler("apply_patch", ToolHandlerKind::ApplyPatch);
     }
 
-    if config
-        .experimental_supported_tools
-        .iter()
-        .any(|tool| tool == "list_dir")
+    if config.has_environment
+        && config
+            .experimental_supported_tools
+            .iter()
+            .any(|tool| tool == "list_dir")
     {
         plan.push_spec(
             create_list_dir_tool(),
@@ -331,14 +336,16 @@ pub fn build_tool_registry_plan(
         );
     }
 
-    plan.push_spec(
-        create_view_image_tool(ViewImageToolOptions {
-            can_request_original_image_detail: config.can_request_original_image_detail,
-        }),
-        /*supports_parallel_tool_calls*/ true,
-        config.code_mode_enabled,
-    );
-    plan.register_handler("view_image", ToolHandlerKind::ViewImage);
+    if config.has_environment {
+        plan.push_spec(
+            create_view_image_tool(ViewImageToolOptions {
+                can_request_original_image_detail: config.can_request_original_image_detail,
+            }),
+            /*supports_parallel_tool_calls*/ true,
+            config.code_mode_enabled,
+        );
+        plan.register_handler("view_image", ToolHandlerKind::ViewImage);
+    }
 
     if config.collab_tools {
         if config.multi_agent_v2 {

codex-rs/tools/src/tool_registry_plan_tests.rs

@@ -453,6 +453,42 @@ fn view_image_tool_includes_detail_with_original_detail_feature() {
     assert!(description.contains("omit this field for default resized behavior"));
 }
 
+#[test]
+fn disabled_environment_omits_environment_backed_tools() {
+    let model_info = model_info();
+    let mut features = Features::with_defaults();
+    features.enable(Feature::UnifiedExec);
+    features.enable(Feature::JsRepl);
+    let available_models = Vec::new();
+    let mut tools_config = ToolsConfig::new(&ToolsConfigParams {
+        model_info: &model_info,
+        available_models: &available_models,
+        features: &features,
+        web_search_mode: Some(WebSearchMode::Cached),
+        session_source: SessionSource::Cli,
+        sandbox_policy: &SandboxPolicy::DangerFullAccess,
+        windows_sandbox_level: WindowsSandboxLevel::Disabled,
+    })
+    .with_has_environment(/*has_environment*/ false);
+    tools_config
+        .experimental_supported_tools
+        .push("list_dir".to_string());
+    let (tools, _) = build_specs(
+        &tools_config,
+        /*mcp_tools*/ None,
+        /*app_tools*/ None,
+        &[],
+    );
+
+    assert_lacks_tool_name(&tools, "exec_command");
+    assert_lacks_tool_name(&tools, "write_stdin");
+    assert_lacks_tool_name(&tools, "js_repl");
+    assert_lacks_tool_name(&tools, "js_repl_reset");
+    assert_lacks_tool_name(&tools, "apply_patch");
+    assert_lacks_tool_name(&tools, "list_dir");
+    assert_lacks_tool_name(&tools, VIEW_IMAGE_TOOL_NAME);
+}
+
 #[test]
 fn test_build_specs_agent_job_worker_tools_enabled() {
     let model_info = model_info();