Add step 625 tool call visualization model

editor/src/AgentChatPanelModel.h

@@ -1,6 +1,8 @@
 #pragma once
 // Step 624: Agent Chat Panel model
 
+#include "AgentToolCallVisualization.h"
+
 #include <cctype>
 #include <string>
 #include <vector>
@@ -19,6 +21,7 @@ struct AgentChatMessage {
 
 struct AgentChatState {
     std::vector<AgentChatMessage> messages;
+    std::vector<AgentToolCallView> toolCalls;
     std::string draftInput;
     bool autoScroll = true;
     bool open = false;
@@ -52,6 +55,20 @@ public:
         state->autoScroll = true;
     }
 
+    static void addToolCall(AgentChatState* state,
+                            const std::string& toolName,
+                            const json& input,
+                            const json& output,
+                            const std::string& timestamp) {
+        if (!state) return;
+        AgentToolCallView view = AgentToolCallVisualization::build(toolName, input, output);
+        state->toolCalls.push_back(view);
+        state->messages.push_back({AgentChatRole::Tool,
+                                   AgentToolCallVisualization::inlineLabel(view),
+                                   timestamp});
+        state->autoScroll = true;
+    }
+
     static const char* roleLabel(AgentChatRole role) {
         if (role == AgentChatRole::User) return "user";
         if (role == AgentChatRole::Assistant) return "assistant";

editor/src/AgentToolCallVisualization.h

@@ -0,0 +1,63 @@
+#pragma once
+// Step 625: Tool call visualization model
+
+#include <nlohmann/json.hpp>
+
+#include <string>
+
+using json = nlohmann::json;
+
+struct AgentToolCallView {
+    std::string toolName;
+    std::string summary;
+    std::string inputJson;
+    std::string outputJson;
+    bool expanded = false;
+};
+
+class AgentToolCallVisualization {
+public:
+    static AgentToolCallView build(const std::string& toolName,
+                                   const json& input,
+                                   const json& output) {
+        AgentToolCallView view;
+        view.toolName = toolName;
+        view.summary = summarize(toolName, input);
+        view.inputJson = input.dump(2);
+        view.outputJson = output.dump(2);
+        return view;
+    }
+
+    static std::string inlineLabel(const AgentToolCallView& view) {
+        const std::string chevron = view.expanded ? "v" : ">";
+        return "[TOOL: " + view.toolName + "] " + chevron + " " + view.summary;
+    }
+
+    static void toggleExpanded(AgentToolCallView* view) {
+        if (!view) return;
+        view->expanded = !view->expanded;
+    }
+
+private:
+    static std::string summarize(const std::string& toolName, const json& input) {
+        if (toolName == "whetstone_mutate") {
+            std::string type = input.value("type", "mutation");
+            std::string nodeId = input.value("nodeId", "?");
+            std::string property = input.value("property", "");
+            std::string value = input.contains("value") ? input["value"].dump() : "null";
+            if (!property.empty()) return type + " " + nodeId + "." + property + " -> " + value;
+            return type + " " + nodeId + " -> " + value;
+        }
+        if (toolName == "whetstone_generate_code") {
+            std::string spec = input.value("spec", "");
+            if (spec.size() > 40) spec = spec.substr(0, 40) + "...";
+            return "generate from spec: " + spec;
+        }
+        if (toolName == "whetstone_run_pipeline") {
+            std::string src = input.value("sourceLanguage", "?");
+            std::string tgt = input.value("targetLanguage", "?");
+            return "pipeline " + src + " -> " + tgt;
+        }
+        return "call";
+    }
+};

editor/src/panels/AgentChatPanel.h

@@ -25,6 +25,28 @@ static void renderAgentChatPanel(EditorState& state) {
     chat.autoScroll = false;
     ImGui::EndChild();
 
+    if (!chat.toolCalls.empty()) {
+        ImGui::Separator();
+        ImGui::TextUnformatted("Tool Calls");
+        for (std::size_t i = 0; i < chat.toolCalls.size(); ++i) {
+            auto& call = chat.toolCalls[i];
+            std::string label = AgentToolCallVisualization::inlineLabel(call);
+            if (ImGui::CollapsingHeader((label + "##tool_" + std::to_string(i)).c_str())) {
+                call.expanded = true;
+                ImGui::TextUnformatted("Input");
+                ImGui::BeginChild(("##tool_in_" + std::to_string(i)).c_str(), ImVec2(-1, 70), true);
+                ImGui::TextUnformatted(call.inputJson.c_str());
+                ImGui::EndChild();
+                ImGui::TextUnformatted("Output");
+                ImGui::BeginChild(("##tool_out_" + std::to_string(i)).c_str(), ImVec2(-1, 70), true);
+                ImGui::TextUnformatted(call.outputJson.c_str());
+                ImGui::EndChild();
+            } else {
+                call.expanded = false;
+            }
+        }
+    }
+
     ImGuiInputTextFlags flags = ImGuiInputTextFlags_AllowTabInput;
     InputTextMultilineStr("##AgentChatInput", &chat.draftInput, ImVec2(-90, 80), flags);
     ImGui::SameLine();