feat: CCSDK sync 2025-12-13 (#21)

- TaskConfig parity (SEP-1686)
- Fix Windows build; stabilize streaming tests
- Normalize outputSchema + structuredContent for FastMCP handler

Author: 0xeb

CMakeLists.txt

@@ -48,6 +48,11 @@ target_include_directories(fastmcpp_core PUBLIC
 # Version header is public
 target_compile_definitions(fastmcpp_core PUBLIC FASTMCPP_VERSION_MAJOR=${PROJECT_VERSION_MAJOR} FASTMCPP_VERSION_MINOR=${PROJECT_VERSION_MINOR} FASTMCPP_VERSION_PATCH=${PROJECT_VERSION_PATCH})
 
+# MSVC: avoid parallel compilation PDB contention (C1041) in large targets
+if(MSVC)
+  target_compile_options(fastmcpp_core PRIVATE /FS)
+endif()
+
 # nlohmann_json dependency - use existing target if available (e.g., from vcpkg)
 if(NOT TARGET nlohmann_json::nlohmann_json)
     include(FetchContent)

include/fastmcpp/client/types.hpp

@@ -60,6 +60,7 @@ struct ToolInfo
     std::optional<std::string> description;
     fastmcpp::Json inputSchema;                       ///< JSON Schema for tool input
     std::optional<fastmcpp::Json> outputSchema;       ///< JSON Schema for structured output
+    std::optional<fastmcpp::Json> execution;          ///< Execution config (SEP-1686)
     std::optional<std::vector<fastmcpp::Icon>> icons; ///< Icons for UI display
 };
 
@@ -323,6 +324,8 @@ inline void to_json(fastmcpp::Json& j, const ToolInfo& t)
         j["description"] = *t.description;
     if (t.outputSchema)
         j["outputSchema"] = *t.outputSchema;
+    if (t.execution)
+        j["execution"] = *t.execution;
     if (t.icons)
         j["icons"] = *t.icons;
 }
@@ -337,6 +340,8 @@ inline void from_json(const fastmcpp::Json& j, ToolInfo& t)
     t.inputSchema = j.value("inputSchema", fastmcpp::Json::object());
     if (j.contains("outputSchema"))
         t.outputSchema = j["outputSchema"];
+    if (j.contains("execution"))
+        t.execution = j["execution"];
     if (j.contains("icons"))
         t.icons = j["icons"].get<std::vector<fastmcpp::Icon>>();
 }

include/fastmcpp/prompts/prompt.hpp

@@ -31,7 +31,8 @@ struct Prompt
     std::string name;
     std::optional<std::string> description;
     std::vector<PromptArgument> arguments;
-    std::function<std::vector<PromptMessage>(const Json&)> generator; // Message generator
+    std::function<std::vector<PromptMessage>(const Json&)> generator;     // Message generator
+    fastmcpp::TaskSupport task_support{fastmcpp::TaskSupport::Forbidden}; // SEP-1686 task mode
 
     // Legacy constructor for backwards compatibility
     Prompt() = default;

include/fastmcpp/resources/resource.hpp

@@ -26,6 +26,7 @@ struct Resource
     std::optional<std::string> description;               // Optional description
     std::optional<std::string> mime_type;                 // MIME type hint
     std::function<ResourceContent(const Json&)> provider; // Content provider function
+    fastmcpp::TaskSupport task_support{fastmcpp::TaskSupport::Forbidden}; // SEP-1686 task mode
 
     // Legacy fields (for backwards compatibility)
     fastmcpp::Id id;

include/fastmcpp/tools/tool.hpp

@@ -18,21 +18,24 @@ class Tool
 
     // Original constructor (backward compatible)
     Tool(std::string name, fastmcpp::Json input_schema, fastmcpp::Json output_schema, Fn fn,
-         std::vector<std::string> exclude_args = {})
+         std::vector<std::string> exclude_args = {},
+         fastmcpp::TaskSupport task_support = fastmcpp::TaskSupport::Forbidden)
         : name_(std::move(name)), input_schema_(std::move(input_schema)),
           output_schema_(std::move(output_schema)), fn_(std::move(fn)),
-          exclude_args_(std::move(exclude_args))
+          exclude_args_(std::move(exclude_args)), task_support_(task_support)
     {
     }
 
     // Extended constructor with title, description, icons
     Tool(std::string name, fastmcpp::Json input_schema, fastmcpp::Json output_schema, Fn fn,
          std::optional<std::string> title, std::optional<std::string> description,
          std::optional<std::vector<fastmcpp::Icon>> icons,
-         std::vector<std::string> exclude_args = {})
+         std::vector<std::string> exclude_args = {},
+         fastmcpp::TaskSupport task_support = fastmcpp::TaskSupport::Forbidden)
         : name_(std::move(name)), title_(std::move(title)), description_(std::move(description)),
           input_schema_(std::move(input_schema)), output_schema_(std::move(output_schema)),
-          icons_(std::move(icons)), fn_(std::move(fn)), exclude_args_(std::move(exclude_args))
+          icons_(std::move(icons)), fn_(std::move(fn)), exclude_args_(std::move(exclude_args)),
+          task_support_(task_support)
     {
     }
 
@@ -67,6 +70,11 @@ class Tool
         return fn_(input);
     }
 
+    fastmcpp::TaskSupport task_support() const
+    {
+        return task_support_;
+    }
+
     // Setters for optional fields (builder pattern)
     Tool& set_title(std::string title)
     {
@@ -83,6 +91,11 @@ class Tool
         icons_ = std::move(icons);
         return *this;
     }
+    Tool& set_task_support(fastmcpp::TaskSupport support)
+    {
+        task_support_ = support;
+        return *this;
+    }
 
   private:
     fastmcpp::Json prune_schema(const fastmcpp::Json& schema) const
@@ -126,6 +139,7 @@ class Tool
     std::optional<std::vector<fastmcpp::Icon>> icons_;
     Fn fn_;
     std::vector<std::string> exclude_args_;
+    fastmcpp::TaskSupport task_support_{fastmcpp::TaskSupport::Forbidden};
 };
 
 } // namespace fastmcpp::tools

include/fastmcpp/types.hpp

@@ -9,6 +9,38 @@ namespace fastmcpp
 
 using Json = nlohmann::json;
 
+/// Background task execution support mode (SEP-1686).
+/// Mirrors fastmcp.server.tasks.TaskConfig.mode / MCP ToolExecution.taskSupport.
+enum class TaskSupport
+{
+    Forbidden, ///< No task augmentation allowed
+    Optional,  ///< Task augmentation supported but not required
+    Required   ///< Task augmentation required
+};
+
+inline std::string to_string(TaskSupport support)
+{
+    switch (support)
+    {
+    case TaskSupport::Forbidden:
+        return "forbidden";
+    case TaskSupport::Optional:
+        return "optional";
+    case TaskSupport::Required:
+        return "required";
+    }
+    return "forbidden";
+}
+
+inline TaskSupport task_support_from_string(const std::string& s)
+{
+    if (s == "optional")
+        return TaskSupport::Optional;
+    if (s == "required")
+        return TaskSupport::Required;
+    return TaskSupport::Forbidden;
+}
+
 struct Id
 {
     std::string value;

src/app.cpp

@@ -166,7 +166,11 @@ std::vector<client::ToolInfo> FastMCP::list_all_tools_info() const
         info.inputSchema = tool.input_schema();
         info.title = tool.title();
         info.description = tool.description();
-        info.outputSchema = tool.output_schema();
+        auto out_schema = tool.output_schema();
+        if (!out_schema.is_null())
+            info.outputSchema = out_schema;
+        if (tool.task_support() != TaskSupport::Forbidden)
+            info.execution = Json{{"taskSupport", to_string(tool.task_support())}};
         info.icons = tool.icons();
         result.push_back(info);
     }