Added tool calling support (#731)

Co-authored-by: krut_ni <nils.kruthoff@dlr.de>
Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

AGENTS.md

@@ -164,6 +164,19 @@ When adding configuration plugin capabilities:
 - For live plugin content, add a data type implementing `ILivePluginContent`, parse it in `PluginConfiguration`, expose it through `PluginFactory`, and add any required cleanup only for persistent side data.
 - Always document the new capability in `app/MindWork AI Studio/Plugins/configuration/plugin.lua`.
 
+## Tool Calling System
+
+**Documentation:** `documentation/Tools.md`
+
+When adding, changing, or removing model-driven tools, keep these parts in sync:
+- `app/MindWork AI Studio/Tools/ToolCallingSystem/ToolCallingImplementations/` for the `IToolImplementation` class, which states its own `ToolDefinition` through `GetDefinition()`, written with `ToolSettingsSchemaBuilder` for its settings and `ToolParameterSchemaBuilder` for the arguments the model passes. There are no tool definition files; a tool arriving from elsewhere brings an `IToolDefinitionSource` instead.
+- `app/MindWork AI Studio/Program.cs` for DI registration of the implementation. Registering it as an `IToolImplementation` is enough, because `CodeToolDefinitionSource` collects the definitions of all of them.
+- `app/MindWork AI Studio/Tools/ToolCallingSystem/ToolSelectionRules.cs` when the shared tool-call limits change. A tool's own minimum provider confidence belongs in its definition, not here.
+- `app/MindWork AI Studio/Tools/ToolCallingSystem/ToolSettingsOptionSources.cs` when a tool setting offers a fixed choice the app maintains, such as languages. Prefer this over spelling the values out in the settings schema; it keeps the list in one place and gives the user translated names.
+- `app/MindWork AI Studio/Plugins/configuration/plugin.lua` to document each setting's field name, meaning, and data type. Tool settings need no code to be centrally manageable: an organization addresses them by `"<toolId>.<fieldName>"` in `DataTools.LockedToolSettings` or `DataTools.DefaultToolSettings`.
+
+Tool implementations must treat model-provided arguments as untrusted input. Validate settings and arguments, protect secrets with `SensitiveTraceArgumentNames`, use `ToolExecutionBlockedException` for intentional policy blocks, and check provider confidence before returning sensitive data to the model.
+
 ## RAG (Retrieval-Augmented Generation)
 
 RAG integration is currently in development (preview feature). Architecture:
@@ -262,4 +275,4 @@ following words:
 - Downgraded
 - Upgraded
 
-The entire changelog is sorted by these categories in the order shown above. The language used for the changelog is US English.
+The entire changelog is sorted by these categories in the order shown above. The language used for the changelog is US English.