Phase 5: MCP 薄殼（search_wiki/read_page）+ BM25 檢索 + 三個 Copilot Custom Agents

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tools/selfcheck_search.py

@@ -0,0 +1,88 @@
+"""Phase 5 自檢：BM25 檢索排序、MCP search_wiki / read_page、
+路徑跳脫防護（信任邊界）、token 上限截斷。
+
+執行：.venv/Scripts/python tools/selfcheck_search.py
+"""
+import os
+import pathlib
+import shutil
+import sys
+import tempfile
+
+sys.path.insert(0, str(pathlib.Path(__file__).parent))
+import kb
+import search
+
+CFG = """ollama: {base_url: "http://localhost:11434", timeout_seconds: 5}
+tasks:
+  ingest: {model: "fake:test", temperature: 0.2, max_retries: 2}
+  lint: {model: "fake:test", temperature: 0.1, max_retries: 2}
+  fallback: {model: "fake:fb"}
+limits: {mcp_response_max_tokens: 100, ingest_chunk_max_chars: 12000}
+"""
+
+
+def page(root, rel, title, desc, tags, body):
+    meta = {"type": {"summaries": "summary", "entities": "entity",
+                     "concepts": "concept"}[rel.split("/")[1]],
+            "title": title, "description": desc, "tags": tags,
+            "timestamp": "2026-07-14", "sources": ["raw/converted/x.md#abcd1234"],
+            "status": "draft"}
+    (root / rel).write_text(kb.dump_page(meta, body), encoding="utf-8")
+
+
+def main():
+    tmp = pathlib.Path(tempfile.mkdtemp(prefix="ppqa-search-"))
+    try:
+        root = tmp / "repo"
+        for sub in ("config", "wiki/summaries", "wiki/entities", "wiki/concepts"):
+            (root / sub).mkdir(parents=True)
+        (root / "config/models.yaml").write_text(CFG, encoding="utf-8")
+        page(root, "wiki/entities/payment-gateway.md", "支付閘道", "支付閘道模組",
+             ["gateway"], "壓力測試時出現逾時缺陷，重試機制未生效。")
+        page(root, "wiki/concepts/aml-testing.md", "AML 測試準則", "可疑交易監控測試綜合",
+             ["aml", "compliance"], "大額交易與分散交易樣態的監控測試要求。")
+        page(root, "wiki/summaries/long-doc.md", "長文件摘要", "截斷測試用",
+             ["test"], "逾時。" * 500)
+
+        hits = search.search(root, "支付閘道 逾時")
+        assert hits and hits[0]["path"] == "wiki/entities/payment-gateway.md", hits
+        assert all(h["score"] > 0 for h in hits)
+        hits2 = search.search(root, "可疑交易監控")
+        assert hits2[0]["path"] == "wiki/concepts/aml-testing.md", hits2
+        assert search.search(root, "zzz-nonexistent-term") == []
+        print("PASS: BM25 檢索排序（繁中 bigram）")
+
+        os.environ["PP_QA_ROOT"] = str(root)
+        import importlib
+        sys.path.insert(0, str(pathlib.Path(__file__).parents[1] / "mcp"))
+        server = importlib.import_module("server")
+        res = server.search_wiki("支付閘道 逾時", top_k=99)  # top_k 超限 → 收斂為 10
+        assert res[0]["path"] == "wiki/entities/payment-gateway.md"
+        pg = server.read_page("wiki/entities/payment-gateway.md")
+        assert pg["frontmatter"]["title"] == "支付閘道" and not pg["truncated"]
+        assert pg["source_refs"] == ["raw/converted/x.md#abcd1234"]
+        long = server.read_page("wiki/summaries/long-doc.md")
+        assert long["truncated"] and len(long["body"]) <= 150 and long["source_refs"]
+        print("PASS: MCP search_wiki + read_page（含 token 截斷、source_refs 保留）")
+
+        for bad in ("../AGENTS.md", "wiki/../config/models.yaml", "wiki/entities/x.txt"):
+            try:
+                server.read_page(bad)
+                raise AssertionError(f"應拒絕：{bad}")
+            except (ValueError, FileNotFoundError) as e:
+                assert isinstance(e, ValueError), f"{bad} 應為 ValueError"
+        try:
+            server.read_page("wiki/entities/no-such.md")
+            raise AssertionError("應拋 FileNotFoundError")
+        except FileNotFoundError:
+            pass
+        print("PASS: 路徑跳脫防護（信任邊界）")
+        print("ALL PASS")
+    finally:
+        os.environ.pop("PP_QA_ROOT", None)
+        shutil.rmtree(tmp, ignore_errors=True)
+
+
+if __name__ == "__main__":
+    main()