server: add built-in tools backend support (#20898)

* wip: server_tools

* refactor

* displayName -> display_name

* snake_case everywhere

* rm redundant field

* change arg to --tools all

* add readme mention

* llama-gen-docs

common/arg.cpp

@@ -2843,6 +2843,15 @@ common_params_context common_params_parser_init(common_params & params, llama_ex
             params.webui_mcp_proxy = value;
         }
     ).set_examples({LLAMA_EXAMPLE_SERVER}).set_env("LLAMA_ARG_WEBUI_MCP_PROXY"));
+    add_opt(common_arg(
+        {"--tools"}, "TOOL1,TOOL2,...",
+        "experimental: whether to enable built-in tools for AI agents - do not enable in untrusted environments (default: no tools)\n"
+        "specify \"all\" to enable all tools\n"
+        "available tools: read_file, file_glob_search, grep_search, exec_shell_command, write_file, edit_file, apply_diff",
+        [](common_params & params, const std::string & value) {
+            params.server_tools = parse_csv_row(value);
+        }
+    ).set_examples({LLAMA_EXAMPLE_SERVER}).set_env("LLAMA_ARG_TOOLS"));
     add_opt(common_arg(
         {"--webui"},
         {"--no-webui"},

common/common.h

@@ -613,6 +613,9 @@ struct common_params {
     bool endpoint_props   = false; // only control POST requests, not GET
     bool endpoint_metrics = false;
 
+    // enable built-in tools
+    std::vector<std::string> server_tools;
+
     // router server configs
     std::string models_dir    = ""; // directory containing models for the router server
     std::string models_preset = ""; // directory containing model presets for the router server