docs(agents): tier3 prompt — read docs FIRST, ban list in Task Start Checklist

.opencode/agents/tier3-worker.md

@@ -35,6 +35,8 @@ DO NOT use native `edit` or `write` tools on Python files.
 You operate statelessly. Each task starts fresh with only the context provided.
 Do not assume knowledge from previous tasks or sessions.
 
+**However (added 2026-06-27):** the canonical conventions for this codebase are in the docs. Read them BEFORE implementing, especially the LLM Default Anti-Patterns in `conductor/code_styleguides/python.md` §17. If you are unsure whether a pattern is allowed (e.g., "is `dict[str, Any]` OK here?"), read the doc; don't guess. LLMs of today are not good enough at predicting what code quality/behavior this project wants — so read the docs.
+
 ## CRITICAL: MCP Tools Only (Native Tools Banned)
 
 You MUST use Manual Slop's MCP tools. Native OpenCode tools are unreliable.
@@ -82,10 +84,21 @@ This is NOT optional. It is the difference between recoverable and catastrophic
 
 Before implementing:
 
-1. [ ] Read task prompt - identify WHERE/WHAT/HOW/SAFETY
+1. [ ] Read the task prompt — identify WHERE/WHAT/HOW/SAFETY
-2. [ ] Use skeleton tools for files >50 lines (`manual-slop_py_get_skeleton`, `manual-slop_get_file_summary`)
+2. [ ] Read the relevant section of `conductor/code_styleguides/python.md` §17 (LLM Default Anti-Patterns) — the bans
-3. [ ] Verify target file and line range exists
+3. [ ] Read `conductor/code_styleguides/data_oriented_design.md` §8.5 — the Python Type Promotion Mandate
-4. [ ] Announce: "Implementing: [task description]"
+4. [ ] Use skeleton tools for files >50 lines (`manual-slop_py_get_skeleton`, `manual-slop_get_file_summary`)
+5. [ ] Verify target file and line range exists
+6. [ ] Announce: "Implementing: [task description]"
+
+**Do NOT introduce these patterns (banned in non-boundary code):**
+- `dict[str, Any]` parameter/return/field types (use typed `@dataclass(frozen=True, slots=True)`)
+- `Any` types (use the concrete typed dataclass)
+- `Optional[T]` returns (use `Result[T]` + `NIL_T` sentinels)
+- `hasattr()` for entity type dispatch (use typed Union or per-entity function)
+- Local imports inside functions (top-of-module imports only)
+- `import X as _PREFIX` aliasing (use the original name)
+- Repeated `.from_dict()` calls in the same expression (cache the result or promote the type)
 
 ## Task Execution Protocol (MANDATORY TDD)