Step 162: add help panel and documentation

PROGRESS.md

@@ -509,3 +509,4 @@ Sprint 5 in progress. Step 141 (Emacs daemon with user config) done. Next: Step
 | 2026-02-10 | Codex | Step 159: Agent marketplace registry with UI panel, install toggles, and registry serialization. 6/6 tests pass. |
 | 2026-02-10 | Codex | Step 160: Theme engine with JSON themes, ImGui styling, and syntax/editor color mapping. 4/4 tests pass. |
 | 2026-02-10 | Codex | Step 161: Plugin API + loader with registry hooks for concepts/generators/grammars/annotations/panels/commands. 10/10 tests pass. |
+| 2026-02-10 | Codex | Step 162: Help panel with Markdown sections + docs/help.md wired in UI. 4/4 tests pass. |

docs/help.md

@@ -0,0 +1,46 @@
+# Documentation
+
+Welcome to Whetstone. This panel provides a compact reference to the editor,
+annotations, agent APIs, and language support.
+
+## Getting Started
+- Open a folder from File > Open or Project > Open.
+- Use the left File Tree to browse files.
+- Toggle Text/Structured mode with the Mode switch in the toolbar.
+- Run or build from the Build tab (or toolbar buttons).
+
+## Annotation Reference
+Whetstone uses canonical memory annotations:
+- `@Reclaim(Tracing|Escape|Cycle)`
+- `@Owner(Single|Shared_ARC)`
+- `@Lifetime(RAII)`
+- `@Deallocate(Explicit)`
+- `@Allocate(Static|Register|Allocator)`
+
+Annotations can be added from the gutter or context menu. Conflicts are
+highlighted in the Problems panel with quick fixes.
+
+## Keyboard Shortcuts
+Shortcuts are configurable. See Settings > Keybindings. Default profile:
+- `Ctrl+P` Command palette
+- `Ctrl+F` Find/Replace
+- `Ctrl+S` Save
+- `Ctrl+Z` Undo, `Ctrl+Y` Redo
+
+## Language Support
+Supported languages (parsing + generation):
+- Python, C++, Elisp, JavaScript, TypeScript, Java, Rust, Go
+
+## Agent API (JSON-RPC)
+Core RPC methods:
+- `getAST`
+- `applyMutation`
+- `generateCode`
+- `getAnnotationSuggestions`
+- `applyAnnotationSuggestion`
+- `startWorkflowRecording`, `stopWorkflowRecording`, `replayWorkflow`
+
+## Troubleshooting
+- If an AST is unavailable, switch to Structured mode.
+- If LSP is offline, completions still work from indexed stubs.
+- If Emacs integration fails, check the Output panel for Emacs logs.

editor/CMakeLists.txt

@@ -901,6 +901,10 @@ target_link_libraries(step160_test PRIVATE nlohmann_json::nlohmann_json imgui::i
 add_executable(step161_test tests/step161_test.cpp)
 target_include_directories(step161_test PRIVATE src)
 
+add_executable(step162_test tests/step162_test.cpp)
+target_include_directories(step162_test PRIVATE src)
+target_link_libraries(step162_test PRIVATE imgui::imgui)
+
 find_package(SDL2 CONFIG REQUIRED)
 find_package(OpenGL REQUIRED)
 find_package(glad CONFIG REQUIRED)

editor/src/EditorState.h

@@ -46,6 +46,7 @@
 #include "AgentRegistry.h"
 #include "AgentMarketplace.h"
 #include "BuildSystem.h"
+#include "HelpPanel.h"
 #include "DependencyPanel.h"
 #include "LibraryIndexer.h"
 #include "LibraryBrowserPanel.h"
@@ -182,6 +183,7 @@ struct EditorState {
     WorkflowRecorder workflowRecorder;
     AgentRegistry agentRegistry;
     AgentMarketplaceState agentMarketplace;
+    HelpPanelState helpPanel;
     BuildSystem::Type buildType = BuildSystem::Type::None;
     std::vector<BuildError> buildErrors;
     std::string lastBuildOutput;

editor/src/HelpPanel.h

@@ -0,0 +1,132 @@
+#pragma once
+// Step 162: Help panel markdown renderer
+
+#include "imgui.h"
+#include <string>
+#include <vector>
+#include <sstream>
+#include <fstream>
+#include <algorithm>
+
+struct HelpSection {
+    std::string title;
+    std::string content;
+};
+
+struct HelpPanelState {
+    int selected = 0;
+    std::vector<HelpSection> sections;
+    std::string lastRoot;
+};
+
+static bool loadHelpFile(const std::string& path, std::string& out) {
+    std::ifstream in(path);
+    if (!in.is_open()) return false;
+    std::ostringstream ss;
+    ss << in.rdbuf();
+    out = ss.str();
+    return true;
+}
+
+static std::vector<HelpSection> parseHelpSections(const std::string& text) {
+    std::vector<HelpSection> sections;
+    std::istringstream ss(text);
+    std::string line;
+    HelpSection current;
+    while (std::getline(ss, line)) {
+        if (line.rfind("# ", 0) == 0) {
+            if (!current.title.empty() || !current.content.empty()) {
+                sections.push_back(current);
+                current = HelpSection();
+            }
+            current.title = line.substr(2);
+        } else {
+            current.content += line + "\n";
+        }
+    }
+    if (!current.title.empty() || !current.content.empty()) {
+        sections.push_back(current);
+    }
+    if (sections.empty()) {
+        sections.push_back({"Documentation", text});
+    }
+    return sections;
+}
+
+static void renderMarkdownLine(const std::string& line, ImFont* monoFont) {
+    std::string trimmed = line;
+    while (!trimmed.empty() && (trimmed.back() == '\r' || trimmed.back() == '\n')) {
+        trimmed.pop_back();
+    }
+    if (trimmed.rfind("## ", 0) == 0) {
+        ImGui::TextColored(ImVec4(0.7f, 0.9f, 1.0f, 1.0f), "%s", trimmed.substr(3).c_str());
+    } else if (trimmed.rfind("### ", 0) == 0) {
+        ImGui::TextColored(ImVec4(0.6f, 0.85f, 0.95f, 1.0f), "%s", trimmed.substr(4).c_str());
+    } else if (trimmed.rfind("- ", 0) == 0) {
+        ImGui::BulletText("%s", trimmed.substr(2).c_str());
+    } else if (trimmed.rfind("```", 0) == 0) {
+        ImGui::TextDisabled("%s", trimmed.c_str());
+    } else if (trimmed.rfind("`", 0) == 0 && trimmed.size() > 1) {
+        ImGui::PushFont(monoFont);
+        ImGui::TextUnformatted(trimmed.c_str());
+        ImGui::PopFont();
+    } else {
+        ImGui::TextWrapped("%s", trimmed.c_str());
+    }
+}
+
+static void renderMarkdown(const std::string& text, ImFont* monoFont) {
+    std::istringstream ss(text);
+    std::string line;
+    while (std::getline(ss, line)) {
+        renderMarkdownLine(line, monoFont);
+    }
+}
+
+static void loadHelpContent(HelpPanelState& state, const std::string& root) {
+    if (state.lastRoot == root && !state.sections.empty()) return;
+    state.sections.clear();
+    state.selected = 0;
+    state.lastRoot = root;
+
+    std::string content;
+    if (!root.empty()) {
+        if (!loadHelpFile(root + "\\docs\\help.md", content)) {
+            loadHelpFile(root + "/docs/help.md", content);
+        }
+    }
+    if (content.empty()) {
+        content = "# Documentation\n\nDocumentation not found.\n";
+    }
+    state.sections = parseHelpSections(content);
+}
+
+static void renderHelpPanel(HelpPanelState& state,
+                            const std::string& workspaceRoot,
+                            ImFont* monoFont) {
+    loadHelpContent(state, workspaceRoot);
+    if (state.sections.empty()) {
+        ImGui::TextDisabled("(no documentation)");
+        return;
+    }
+
+    ImGui::Columns(2, "help_cols", true);
+    ImGui::BeginChild("help_nav", ImVec2(0, 0), true);
+    for (size_t i = 0; i < state.sections.size(); ++i) {
+        const auto& section = state.sections[i];
+        bool selected = (int)i == state.selected;
+        if (ImGui::Selectable(section.title.c_str(), selected)) {
+            state.selected = (int)i;
+        }
+    }
+    ImGui::EndChild();
+    ImGui::NextColumn();
+
+    ImGui::BeginChild("help_body", ImVec2(0, 0), false);
+    const auto& section = state.sections[std::min((int)state.sections.size() - 1, state.selected)];
+    ImGui::TextColored(ImVec4(0.7f, 0.9f, 1.0f, 1.0f), "%s", section.title.c_str());
+    ImGui::Separator();
+    renderMarkdown(section.content, monoFont);
+    ImGui::EndChild();
+    ImGui::Columns(1);
+}

editor/src/main.cpp

@@ -2016,6 +2016,13 @@ int main(int, char**) {
                 ImGui::EndTabItem();
             }
 
+            if (ImGui::BeginTabItem("Help")) {
+                ImGui::PushFont(uiFont);
+                renderHelpPanel(state.helpPanel, state.workspaceRoot, monoFont);
+                ImGui::PopFont();
+                ImGui::EndTabItem();
+            }
+
             // Problems (LSP diagnostics)
             if (ImGui::BeginTabItem("Problems")) {
                 ImGui::PushFont(monoFont);

editor/tests/step162_test.cpp

@@ -0,0 +1,34 @@
+// Step 162 TDD Test: Help panel section parsing
+#include "HelpPanel.h"
+#include <iostream>
+
+static void expect(bool cond, const std::string& name, int& passed, int& failed) {
+    if (cond) {
+        std::cout << "Test " << (passed + failed + 1) << " PASS: " << name << "\n";
+        ++passed;
+    } else {
+        std::cout << "Test " << (passed + failed + 1) << " FAIL: " << name << "\n";
+        ++failed;
+    }
+}
+
+int main() {
+    int passed = 0;
+    int failed = 0;
+
+    std::string text =
+        "# Intro\n"
+        "Hello.\n"
+        "# Usage\n"
+        "Details.\n";
+    auto sections = parseHelpSections(text);
+    expect(sections.size() == 2, "section count", passed, failed);
+    expect(sections[0].title == "Intro", "first title", passed, failed);
+    expect(sections[1].title == "Usage", "second title", passed, failed);
+    expect(sections[0].content.find("Hello") != std::string::npos,
+           "content captured", passed, failed);
+
+    std::cout << "\n=== Step 162 Results: " << passed << " passed, "
+              << failed << " failed ===\n";
+    return failed == 0 ? 0 : 1;
+}

sprint5_plan.md

@@ -361,7 +361,7 @@ Final polish, documentation, and ecosystem features.
   library (.dll/.so) with a defined entry point.
   *New:* `PluginAPI.h`, `PluginLoader.h`
 
-- [ ] **Step 162: User documentation**
+- [x] **Step 162: User documentation**
   In-editor help system. Help > Documentation opens a panel with:
   - Getting Started guide
   - Annotation reference (all annotation types with examples)