diff --git a/PROGRESS.md b/PROGRESS.md
index 947195b..fa46c2b 100644
--- a/PROGRESS.md
+++ b/PROGRESS.md
@@ -747,3 +747,4 @@ vcpkg's imgui 1.91.9 removed the `sdl2-binding` feature (only `sdl3-binding` exi
 | 2026-02-10 | Claude Opus 4.6 | Sprint 7 Phase 7b (Steps 207–213): MCPServer.h (10 tools, 5 resources, 4 prompts, JSON-RPC 2.0 initialize handshake), MCPBridge.h (stdio transport). 90/90 tests pass. |
 | 2026-02-10 | Claude Opus 4.6 | Sprint 7 Phase 7c (Steps 214–219): TraceGenerator.h (6 scenario templates, 9-sample code corpus, batch engine), TraceExporter.h (Anthropic/OpenAI/JSONL/Markdown export, filtering, statistics). 294/294 tests pass. |
 | 2026-02-10 | Codex | Step 227: Open-source model tool definitions (ReAct-style prompt, XML tool call format, simplified schemas, adapter rules). 1/1 tests pass. |
+| 2026-02-10 | Codex | Step 228: Prompt engineering templates (5 prompt files with system/user templates, expected tools, success criteria). 1/1 tests pass. |
diff --git a/editor/CMakeLists.txt b/editor/CMakeLists.txt
index 98f1677..9b7d746 100644
--- a/editor/CMakeLists.txt
+++ b/editor/CMakeLists.txt
@@ -1166,6 +1166,8 @@ add_executable(step226_test tests/step226_test.cpp)
 target_include_directories(step226_test PRIVATE src)
 add_executable(step227_test tests/step227_test.cpp)
 target_include_directories(step227_test PRIVATE src)
+add_executable(step228_test tests/step228_test.cpp)
+target_include_directories(step228_test PRIVATE src)
 add_executable(step213_test tests/step213_test.cpp)
 target_include_directories(step213_test PRIVATE src)
 target_link_libraries(step213_test PRIVATE nlohmann_json::nlohmann_json)
diff --git a/editor/tests/step228_test.cpp b/editor/tests/step228_test.cpp
new file mode 100644
index 0000000..516258b
--- /dev/null
+++ b/editor/tests/step228_test.cpp
@@ -0,0 +1,40 @@
+// Step 228: Prompt engineering templates.
+
+#include <cassert>
+#include <fstream>
+#include <string>
+#include <vector>
+
+static std::string readFile(const std::string& path) {
+    std::ifstream f(path);
+    if (!f.is_open()) return {};
+    return std::string((std::istreambuf_iterator<char>(f)),
+                       std::istreambuf_iterator<char>());
+}
+
+static void assertContains(const std::string& text, const std::string& needle) {
+    assert(text.find(needle) != std::string::npos);
+}
+
+int main() {
+    const std::vector<std::string> prompts = {
+        "../tools/prompts/annotate_module.prompt",
+        "../tools/prompts/cross_language.prompt",
+        "../tools/prompts/code_review.prompt",
+        "../tools/prompts/refactor.prompt",
+        "../tools/prompts/security.prompt"
+    };
+
+    for (const auto& path : prompts) {
+        const std::string content = readFile(path);
+        assert(!content.empty());
+        assertContains(content, "system:");
+        assertContains(content, "user:");
+        assertContains(content, "expected_tools:");
+        assertContains(content, "success_criteria:");
+        assertContains(content, "{{");
+    }
+
+    printf("step228_test: all assertions passed\n");
+    return 0;
+}
diff --git a/sprint7_plan.md b/sprint7_plan.md
index 552f0b8..476f084 100644
--- a/sprint7_plan.md
+++ b/sprint7_plan.md
@@ -375,7 +375,7 @@ Optimized tool definitions and prompts for specific LLM families.
   - Adapter that parses model output into structured tool calls
   *New:* `tools/generic/` directory with definitions + adapter
 
-- [ ] **Step 228: Prompt engineering templates**
+- [x] **Step 228: Prompt engineering templates**
   Reusable prompt templates for common Whetstone tasks:
   - `annotate_module.prompt` — System + user messages for annotation workflow
   - `cross_language.prompt` — System + user for cross-language projection
diff --git a/tools/prompts/annotate_module.prompt b/tools/prompts/annotate_module.prompt
new file mode 100644
index 0000000..a4e936c
--- /dev/null
+++ b/tools/prompts/annotate_module.prompt
@@ -0,0 +1,17 @@
+# annotate_module
+
+system:
+You are a Whetstone annotation assistant. Prefer using tools to inspect ASTs and apply safe annotations.
+
+user:
+Analyze module {{module_name}}. Suggest memory annotations for all unannotated functions. Include confidence scores and reasons.
+
+expected_tools:
+- whetstone_get_ast
+- whetstone_suggest_annotations
+- whetstone_apply_annotation
+
+success_criteria:
+- All unannotated functions receive suggestions.
+- Each suggestion includes a confidence score and brief reason.
+- Applied annotations are reported with node ids.
diff --git a/tools/prompts/code_review.prompt b/tools/prompts/code_review.prompt
new file mode 100644
index 0000000..89f4850
--- /dev/null
+++ b/tools/prompts/code_review.prompt
@@ -0,0 +1,16 @@
+# code_review
+
+system:
+You are a Whetstone reviewer. Inspect AST and annotations before giving recommendations.
+
+user:
+Review module {{module_name}} for annotation correctness. Highlight risky memory strategies and suggest safer alternatives.
+
+expected_tools:
+- whetstone_get_ast
+- whetstone_suggest_annotations
+
+success_criteria:
+- Risks are tied to specific nodes.
+- Safer alternatives are provided with rationale.
+- No changes are applied unless explicitly requested.
diff --git a/tools/prompts/cross_language.prompt b/tools/prompts/cross_language.prompt
new file mode 100644
index 0000000..9920efb
--- /dev/null
+++ b/tools/prompts/cross_language.prompt
@@ -0,0 +1,16 @@
+# cross_language
+
+system:
+You are a Whetstone projection assistant. Use the pipeline tools to convert between languages while preserving annotations.
+
+user:
+Project the current module from {{source_language}} to {{target_language}}. Keep annotation intent equivalent and report adaptation notes.
+
+expected_tools:
+- whetstone_get_ast
+- whetstone_project_language
+
+success_criteria:
+- Target language projection produced.
+- Annotation adaptation notes include any strategy changes.
+- Output includes the projected AST summary.
diff --git a/tools/prompts/refactor.prompt b/tools/prompts/refactor.prompt
new file mode 100644
index 0000000..d79de57
--- /dev/null
+++ b/tools/prompts/refactor.prompt
@@ -0,0 +1,17 @@
+# refactor
+
+system:
+You are a Whetstone refactoring assistant. Use AST mutations in small, verifiable steps.
+
+user:
+Refactor {{module_name}} to {{goal}}. Keep behavior intact and update annotations if ownership changes.
+
+expected_tools:
+- whetstone_get_ast
+- whetstone_mutate
+- whetstone_batch_mutate
+
+success_criteria:
+- Refactor uses minimal, reversible mutations.
+- Behavior preserved per description.
+- Annotation updates reflect new ownership.
diff --git a/tools/prompts/security.prompt b/tools/prompts/security.prompt
new file mode 100644
index 0000000..536fc75
--- /dev/null
+++ b/tools/prompts/security.prompt
@@ -0,0 +1,16 @@
+# security
+
+system:
+You are a Whetstone security assistant. Check dependencies and annotations for vulnerabilities before recommending changes.
+
+user:
+Audit {{module_name}} dependencies for known vulnerabilities. Recommend safe upgrades and show impacted functions.
+
+expected_tools:
+- whetstone_get_ast
+- whetstone_get_scope
+
+success_criteria:
+- Vulnerable dependencies are listed.
+- Recommendations include safer versions or alternatives.
+- Impacted nodes or functions are identified.