feat(cpp-object-oriented-modular-refactoring): step 0 - coding-style-agent-contract

.codex/agents/implementation-agent.toml

@@ -21,6 +21,11 @@ Mission:
 Skill references:
 - Use $fesa-cpp-msvc-tdd when writing C++17/MSVC tests first, verifying RED failures, implementing minimal solver code, registering CMake/CTest targets, running validation, or preparing implementation reports.
 
+Mandatory global input:
+- Before every C++ implementation Step, read docs/CODINGSTYLE.md as a mandatory global
+  input and apply it to production and test code.
+- Doxygen coverage applies only to production code.
+
 Mandatory Harness reading:
 - Read .agents/skills/harness/SKILL.md, docs/HARNESS.md, docs/HARNESS_WORKFLOW.md, and
   .codex/hooks.json before executing a Harness Step; inspect the relevant phase indexes and

tests/test_agent_skill_workflow_contract.py

@@ -302,6 +302,23 @@ def test_implementation_steps_keep_final_comparison_in_a_final_gate():
         assert "reference-comparison.md" in text, path
 
 
+def test_p_agent_001_implementation_agent_reads_coding_style_before_cpp_steps():
+    parsed = tomllib.loads(read(AGENT_DIR / "implementation-agent.toml"))
+    instructions = parsed["developer_instructions"]
+    section_match = re.search(
+        r"Mandatory global input:\n(?P<section>.*?)(?=\n[A-Z][^\n]+:\n)",
+        instructions,
+        re.DOTALL,
+    )
+
+    assert section_match is not None
+    section = section_match.group("section")
+    assert "Before every C++ implementation Step" in section
+    assert "read docs/CODINGSTYLE.md" in section
+    assert "apply it to production and test code" in section
+    assert "Doxygen coverage applies only to production code" in section
+
+
 def test_agent_hierarchy_is_explicit():
     coordinator = read(AGENT_DIR / "coordinator-agent.toml").lower()
     assert "main agent" in coordinator