fix(projekt-matching): break infinite alert loop (issue 2)

Root cause chain (evidence: 25+ failed traces on nproj/3022414):
straight quote in page text ends the guided-decoding JSON string
early -> grammar deadlock -> whitespace loop until context/token
limit -> chat_json fails 3x (~35 min) -> IMAP conn idles out ->
move_to_trash raises -> mail never trashed -> reprocessed forever.

- ingest/mailer: MailBox.ensure_alive() reconnect before finalize;
  move_to_trash failure falls back to flag_checked, run continues
- stages: page_text() feeds only div.content minus skill-tag cloud
  to the LLM and maps quote chars to apostrophes (the actual
  degeneration trigger, live-verified: extract now OK in 21 s)
- llm: requirements maxItems 40; max_tokens 8192 caps degenerate
  runs at ~100 s instead of ~10 min

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

projekt-matching/projektmatch/ingest.py

@@ -119,6 +119,10 @@ def run_ingest(cfg, mailbox=None, dispatch=None, espo=None, resolve=None):
                             or f"unbekannter Status: {result.get('status')!r}")
                     results.append(result)
                     summary[result["status"]] += 1
+                try:
+                    box.ensure_alive()  # Flow-2-Dispatches können >30 min dauern — Server-Idle-Timeout
+                except Exception:      # noqa: BLE001
+                    pass               # Alert/Trash unten haben eigene Fallbacks
                 failed = [r for r in results if r["status"] == "failed"]
                 if failed:
                     lines = "\n\n".join(
@@ -134,7 +138,14 @@ def run_ingest(cfg, mailbox=None, dispatch=None, espo=None, resolve=None):
                             "werden:\n\n" + lines + "\n")
                     except Exception:          # noqa: BLE001
                         summary["alertFailed"] = summary.get("alertFailed", 0) + 1
+                try:
                     box.move_to_trash(uid)
+                except Exception:              # noqa: BLE001
+                    summary["trashFailed"] = summary.get("trashFailed", 0) + 1
+                    try:
+                        box.flag_checked(uid)  # nie erneut verarbeiten — Terminal-Zustand
+                    except Exception:          # noqa: BLE001
+                        pass                   # nächster Lauf räumt auf
             return summary
         finally:
             box.close()

projekt-matching/projektmatch/llm.py

@@ -1,7 +1,9 @@
 """vLLM (OpenAI-compatible) calls with response_format json_schema + German prompts.
 
-max_tokens stays UNSET so nothing can truncate the final answer (65k
-context window). Thinking is DISABLED via chat_template_kwargs: with the
+max_tokens is capped at 8192: every valid answer fits comfortably, and an
+uncapped run lets a degenerate generation grind for ~10 min before failing
+(observed live: 100+-requirement JSON, broken at ~char 1725, 3 retries =
+~35 min per cycle). Thinking is DISABLED via chat_template_kwargs: with the
 vLLM qwen3 reasoning parser active, json_schema guided decoding plus
 thinking degenerates — the run burns the entire context window
 (finish_reason "length", ~63k completion tokens) and returns empty or
@@ -34,6 +36,7 @@ EXTRACT_SCHEMA = {
         "contactPerson": {"type": ["string", "null"]},
         "requirements": {
             "type": "array",
+            "maxItems": 40,
             "items": {
                 "type": "object",
                 "properties": {
@@ -139,6 +142,7 @@ z. B. vLLM, TGI, Triton" ab).
 
 def _post(base, model, messages, schema):
     body = {"model": model, "messages": messages, "temperature": 0.1,
+            "max_tokens": 8192,
             "chat_template_kwargs": {"enable_thinking": False},
             "response_format": {"type": "json_schema", "json_schema": {
                 "name": "out", "schema": schema}}}

projekt-matching/projektmatch/mailer.py

@@ -16,12 +16,31 @@ KEYWORD = "$ProjektChecked"
 
 class MailBox:
     def __init__(self, user, password, conn=None):
-        self.conn = conn or imaplib.IMAP4_SSL(IMAP_HOST, IMAP_PORT)
-        if conn is None:
-            self.conn.login(user, password)
+        self.user, self.password = user, password
+        self.conn = conn or self._connect()
         self.conn.select("INBOX")
         self._trash = None
 
+    def _connect(self):
+        conn = imaplib.IMAP4_SSL(IMAP_HOST, IMAP_PORT)
+        conn.login(self.user, self.password)
+        return conn
+
+    def ensure_alive(self):
+        """Reconnect if the server dropped the connection (idle timeout)."""
+        try:
+            typ, _ = self.conn.noop()
+            if typ == "OK":
+                return
+        except Exception:      # noqa: BLE001
+            pass
+        try:
+            self.conn.logout()
+        except Exception:      # noqa: BLE001
+            pass
+        self.conn = self._connect()
+        self.conn.select("INBOX")
+
     def unchecked_uids(self):
         typ, data = self.conn.uid("SEARCH", None, f"UNKEYWORD {KEYWORD}")
         if typ != "OK" or not data or not data[0]:

projekt-matching/projektmatch/stages.py

@@ -20,6 +20,7 @@ TEAM_BY_OFFER = {"Projekt": "DesTEngS",
                  "Arbeitnehmer-Angebot": "Arbeitnehmer",
                  "ANÜ": "ANÜ"}
 MIN_PAGE_CHARS = 200
+QUOTES = str.maketrans({c: "'" for c in "„“”\"«»‹›"})
 
 
 def run_stage(name, fn, ctx, cfg, **kw):
@@ -32,6 +33,25 @@ def run_stage(name, fn, ctx, cfg, **kw):
         return ctx
 
 
+def page_text(html):
+    """Project text for the LLM: header + description, WITHOUT the skill-tag
+    cloud (div.project-body-badges, ~100 entries on some pages — blows the
+    requirements list up until the model emits broken JSON) and without
+    site chrome. Falls back to whole-page text if div.content is missing."""
+    soup = BeautifulSoup(html, "html.parser")
+    for tag in soup(["script", "style", "noscript"]):
+        tag.decompose()
+    root = soup.find("div", class_="content") or soup
+    for tag in root.find_all(class_="project-body-badges"):
+        tag.decompose()
+    # Anführungszeichen -> Apostroph: ein wörtlich übernommenes " beendet den
+    # JSON-String vorzeitig und treibt guided decoding in eine Whitespace-
+    # Endlosschleife (finish_reason "length", live verifiziert an nproj/3022414)
+    return "\n".join(line for line in
+                     root.get_text("\n", strip=True).splitlines()
+                     if line.strip()).translate(QUOTES)
+
+
 def stage_fetch(ctx, cfg):
     last = None
     for attempt in range(3):
@@ -39,12 +59,7 @@ def stage_fetch(ctx, cfg):
             resp = requests.get(ctx["canonical"], timeout=30,
                                 headers={"User-Agent": BROWSER_UA})
             resp.raise_for_status()
-            soup = BeautifulSoup(resp.text, "html.parser")
-            for tag in soup(["script", "style", "noscript"]):
-                tag.decompose()
-            text = "\n".join(line for line in
-                             soup.get_text("\n", strip=True).splitlines()
-                             if line.strip())
+            text = page_text(resp.text)
             if len(text) < MIN_PAGE_CHARS:
                 raise ValueError(
                     f"Seitentext zu kurz ({len(text)} Zeichen) — "

projekt-matching/tests/test_ingest.py

@@ -156,6 +156,63 @@ def test_close_called_even_if_unchecked_uids_raises(tmp_path):
     box.close.assert_called_once()
 
 
+def test_ensure_alive_called_before_finalize(tmp_path):
+    mails = {"1": mail("Mail", PROJECT_HTML)}
+    summary, box, sent = run(tmp_path, mails,
+                             dispatch_result={"status": "failed",
+                                              "error": "Read timed out"})
+    names = [c[0] for c in box.method_calls]
+    assert "ensure_alive" in names
+    assert names.index("ensure_alive") < names.index("move_to_trash")
+    box.move_to_trash.assert_called_once_with("1")
+    assert len(sent) == 1
+
+
+def test_trash_failure_falls_back_to_flag_and_continues(tmp_path):
+    mails = {"1": mail("Mail A", PROJECT_HTML),
+             "2": mail("Mail B", PROJECT_HTML)}
+    box = mock.Mock()
+    box.unchecked_uids.return_value = ["1", "2"]
+    box.fetch.side_effect = lambda uid: mails[uid]
+    box.move_to_trash.side_effect = [OSError("socket error: EOF"), None]
+    espo = mock.Mock()
+    espo.find_opportunity_by_link.return_value = None
+    with mock.patch("projektmatch.ingest.mailparse.bodies",
+                    side_effect=lambda m: (m["html"], "")), \
+         mock.patch("projektmatch.ingest.mailer.send_mail", lambda *a: None):
+        summary = ingest.run_ingest(
+            cfg(tmp_path), mailbox=box, espo=espo,
+            resolve=lambda url: "https://www.freelancermap.de/projekt/eins",
+            dispatch=lambda item: {"status": "created"})
+    assert summary["trashFailed"] == 1
+    assert summary["created"] == 2
+    box.flag_checked.assert_called_once_with("1")
+    assert box.move_to_trash.call_count == 2
+
+
+def test_dead_connection_everywhere_still_finishes_run(tmp_path):
+    mails = {"1": mail("Mail A", PROJECT_HTML),
+             "2": mail("Mail B", PROJECT_HTML)}
+    box = mock.Mock()
+    box.unchecked_uids.return_value = ["1", "2"]
+    box.fetch.side_effect = lambda uid: mails[uid]
+    box.ensure_alive.side_effect = OSError("server unreachable")
+    box.move_to_trash.side_effect = OSError("socket error: EOF")
+    box.flag_checked.side_effect = OSError("socket error: EOF")
+    espo = mock.Mock()
+    espo.find_opportunity_by_link.return_value = None
+    with mock.patch("projektmatch.ingest.mailparse.bodies",
+                    side_effect=lambda m: (m["html"], "")), \
+         mock.patch("projektmatch.ingest.mailer.send_mail", lambda *a: None):
+        summary = ingest.run_ingest(
+            cfg(tmp_path), mailbox=box, espo=espo,
+            resolve=lambda url: "https://www.freelancermap.de/projekt/eins",
+            dispatch=lambda item: {"status": "created"})
+    assert summary["trashFailed"] == 2
+    assert summary["created"] == 2
+    box.close.assert_called_once()
+
+
 def test_parse_run_result_finds_status_json():
     inner = json.dumps({"status": "created", "mustMatch": 90})
     payload = {"outputs": [{"outputs": [{"results": {"text": {

projekt-matching/tests/test_llm.py

@@ -24,11 +24,16 @@ def test_chat_json_strips_think_and_parses():
                             {"type": "object"})
     assert out == {"a": 1}
     body = p.call_args.kwargs["json"]
-    assert "max_tokens" not in body
+    assert body["max_tokens"] == 8192
     assert body["chat_template_kwargs"] == {"enable_thinking": False}
     assert body["response_format"]["json_schema"]["schema"] == {"type": "object"}
 
 
+def test_extract_schema_caps_requirements_list():
+    reqs = llm.EXTRACT_SCHEMA["properties"]["requirements"]
+    assert reqs["maxItems"] == 40
+
+
 def test_chat_json_strips_markdown_fences():
     content = "```json\n{\"a\": 2}\n```"
     with mock.patch("projektmatch.llm.requests.post", fake_post([content])):

projekt-matching/tests/test_mailer.py

@@ -83,6 +83,28 @@ def test_send_mail_survives_append_failure():
         mailer.send_mail("u@x", "pw", "to@x", "Subj", "Body")
 
 
+def test_ensure_alive_keeps_healthy_connection():
+    conn = fake_conn()
+    conn.noop.return_value = ("OK", [b""])
+    box = mailer.MailBox("u", "p", conn=conn)
+    box.ensure_alive()
+    assert box.conn is conn
+    conn.noop.assert_called_once()
+
+
+def test_ensure_alive_reconnects_on_dead_connection():
+    conn = fake_conn()
+    conn.noop.side_effect = OSError("connection closed")
+    box = mailer.MailBox("u", "p", conn=conn)
+    fresh = fake_conn()
+    with mock.patch("projektmatch.mailer.imaplib.IMAP4_SSL",
+                    return_value=fresh):
+        box.ensure_alive()
+    assert box.conn is fresh
+    fresh.login.assert_called_once_with("u", "p")
+    fresh.select.assert_called_once_with("INBOX")
+
+
 def test_append_sent_uses_special_use_folder():
     conn = mock.Mock()
     conn.list.return_value = ("OK", [

projekt-matching/tests/test_stages.py

@@ -33,6 +33,68 @@ def ctx_after_match(ratings):
     return ctx
 
 
+PROJECT_PAGE = """
+<html><body>
+<nav>Login Registrieren</nav>
+<div class="content">
+  <div class="project-header">
+    <h1>ISTQB Testautomatisierung (m/w/d)</h1>
+    <span>iSAX Consulting GmbH</span>
+    <span>Start 8/2026</span>
+  </div>
+  <div class="project-body">
+    <div class="project-body-badges badges-container">
+      <a href="#">ISTQB</a><a href="#">Testsuite</a><a href="#">IBM Aix</a>
+    </div>
+    <div class="project-body-description">
+      <p>Beschreibung: Muss-Anforderungen: 3 Jahre Testautomatisierung.
+      Erstellung, Beratung und methodische Unterstuetzung der Projektteams
+      bei Testkonzept und Teststrategie. Organisation der Testkoordination
+      fuer einen uebergreifenden Test. Durchfuehrung von manuellen und
+      automatisierten Tests sowie Last- und Performancetests.</p>
+    </div>
+  </div>
+</div>
+<footer>Impressum Datenschutz</footer>
+</body></html>
+"""
+
+
+def test_page_text_keeps_header_and_description_drops_tag_cloud():
+    text = stages.page_text(PROJECT_PAGE)
+    assert "ISTQB Testautomatisierung (m/w/d)" in text
+    assert "Start 8/2026" in text
+    assert "Muss-Anforderungen: 3 Jahre Testautomatisierung" in text
+    assert "IBM Aix" not in text
+    assert "Testsuite" not in text
+    assert "Impressum" not in text
+
+
+def test_page_text_replaces_quotes_that_break_json_strings():
+    html = ('<div class="content">Zertifizierung „ISTQB Certified Tester" '
+            'sowie "Scrum" und “Kanban”.</div>')
+    text = stages.page_text(html)
+    assert '"' not in text
+    assert "„" not in text and "“" not in text and "”" not in text
+    assert "'ISTQB Certified Tester'" in text
+
+
+def test_page_text_falls_back_to_whole_page():
+    html = "<html><body><p>Nur Text ohne content-Div.</p></body></html>"
+    assert "Nur Text ohne content-Div." in stages.page_text(html)
+
+
+def test_stage_fetch_uses_project_section():
+    resp = mock.Mock(status_code=200, text=PROJECT_PAGE)
+    resp.raise_for_status = lambda: None
+    ctx = {"canonical": "https://www.freelancermap.de/projekt/x", "title": "t"}
+    with mock.patch("projektmatch.stages.requests.get", return_value=resp):
+        out = stages.stage_fetch(dict(ctx), CFG)
+    assert out["status"] == "ok"
+    assert "IBM Aix" not in out["page_text"]
+    assert "Muss-Anforderungen" in out["page_text"]
+
+
 def test_run_stage_catches_and_skips():
     def boom(ctx, cfg):
         raise ValueError("kaputt")