phase: 113_source_chip_quality

All gates green — no defects found; this pass was verification only.

**Phase 113 final verification pass — report**

- Verified (no code changes needed): `select_documents_tiered` cited/related tiering + `select_documents` wrapper, `TurnPlan.related_docs`, `ChatDoneEvent.related` (additive, old payloads parse), `appendRelated` UI row (`.related-doc`, never `.source-chip`), done-frame + restore-path wiring, two settings with validators, `.env.example` entries
- `uv run pytest --cov=app --cov-report=term-missing` → 2422 passed, app/ coverage **99%** (>90% gate)
- `uv run pytest tests/e2e/test_source_chip_quality.py -v --no-cov` (isolated) → 2 passed
- Regression E2E `test_retrieval_quality.py` + `test_honest_deflection.py` + `test_chat_rag.py` + `test_sources_midstream_bug.py` → 17 passed
- `uv run ruff check . && uv run pyright` → clean (0 errors); `bash .agents/validate.sh` → "validation OK"

Completion criteria:
1. Single-doc question → exactly one `.source-chip` (E2E): ✅ passed
2. Weak 2nd doc only in de-emphasized related row, never `.source-chip` (unit + E2E): ✅ passed
3. Deflected turn → zero citation chips, weak hits in related row: ✅ passed
4. Full suite green, coverage >90%, isolated E2E green, lint/types clean: ✅ passed
5. `--no-gpg-sign` commit + phase dir move: left to harness per pass rules (task files already in `complete/`)

No deviations. Next pending phase: `114_embed_question_length`.

tests/e2e/test_source_chip_quality.py

@@ -0,0 +1,201 @@
+"""Phase 113 E2E (Playwright): the source-chip quality contract (TODO L5 +
+L2c) — the usefulness bar + the de-emphasized related-docs row, as VISIBLE
+chip counts.
+
+Run in isolation (DB must be up: ``podman compose up -d db``):
+
+    uv run pytest tests/e2e/test_source_chip_quality.py -v --no-cov
+
+Acceptance (TODO L144–146): "for a single-document question, the turn
+shows one citation chip"; a weak 2nd doc renders only in the
+de-emphasized related row (``.related-doc`` links, NEVER ``.source-chip``);
+a deflected turn shows zero citation chips (its weak hits, if any, live in
+the related row).
+
+The fixture KB's tier shapes are deterministic under the E2E mock's
+bag-of-words embeddings + the mock-calibrated bar (conftest:
+``BOR_SOURCE_USEFULNESS_FLOOR=0.15``, half the 0.30 threshold — like the
+lexical floor):
+
+* **single-source question** — "What SSH aliases do I have?":
+  ``ssh_aliases.txt`` is the ONLY doc whose best-chunk cosine clears the
+  bar (0.352 ≥ 0.15; grounded at 0.352 ≥ 0.30) → the done frame carries
+  exactly ONE cited ref; the two below-bar docs (gitlab-compose.yaml
+  0.025, uptime_probe.py 0.113) ride the related tier. This IS the
+  strong+weak two-tier shape on the wire (the four OBSERVED live shapes
+  are unit-pinned at plan level in
+  ``tests/unit/test_source_chip_quality.py`` — the fixture KB reproduces
+  the same shape live, so no docstring caveat is needed).
+* **deflected question** — "How do I bake sourdough bread?": best cosine
+  0.109 < 0.30 and zero FTS hits → honest deflection; nothing clears the
+  bar → zero cited refs; the weak hits (new-service.md 0.109,
+  ssh_aliases.txt 0.050) ride the related row.
+"""
+from __future__ import annotations
+
+import asyncio
+from pathlib import Path
+from threading import Thread
+from typing import Any
+
+from playwright.sync_api import Page, expect
+from sqlalchemy import select, text
+
+from app.config import Settings, get_settings
+from app.db import SessionLocal
+from app.models import QueryLog
+from app.rag.importer import ImportSummary, import_sources
+from app.rag.llm import LLMClient
+from e2e.auth_helpers import login
+
+REPO = Path(__file__).resolve().parents[2]
+FIXTURES = REPO / "tests" / "fixtures" / "docs"
+SINGLE_SOURCE_QUESTION = "What SSH aliases do I have?"
+OFF_TOPIC = "How do I bake sourdough bread?"
+MOCK_ANSWER_MARKER = "Deterministic mock answer for E2E"
+
+
+async def _import_fixtures(mock_port: int) -> ImportSummary:
+    kwargs: dict[str, Any] = {"_env_file": None, "llm_base_url": f"http://127.0.0.1:{mock_port}/v1"}
+    settings = Settings(**kwargs)  # pyright: ignore[reportCallIssue]
+    return await import_sources([FIXTURES], LLMClient(settings))
+
+
+def _run_in_thread(coro: Any) -> Any:
+    """Run a coroutine on a worker thread (Playwright owns the test loop)."""
+    box: dict[str, Any] = {}
+
+    def runner() -> None:
+        try:
+            box["value"] = asyncio.run(coro)
+        except BaseException as e:  # noqa: BLE001 — re-raised on the test thread
+            box["error"] = e
+
+    t = Thread(target=runner)
+    t.start()
+    t.join()
+    if "error" in box:
+        raise box["error"]
+    return box["value"]
+
+
+def _reset_db(mock_port: int, seed: bool = True) -> ImportSummary | None:
+    """Truncate the KB (and query log), then optionally re-import fixtures."""
+    with SessionLocal() as db:
+        db.execute(text("TRUNCATE chunks, documents, query_log"))
+        db.commit()
+    if not seed:
+        return None
+    return _run_in_thread(_import_fixtures(mock_port))
+
+
+def _ask(page: Page, message: str) -> None:
+    page.fill("#message-input", message)
+    page.click("#send-btn")
+
+
+def test_single_source_question_shows_exactly_one_citation_chip(
+    page: Page, app_url: str, mock_llm: int, db_ready: None
+) -> None:
+    """The acceptance pin: a single-document question → the done bubble
+    carries EXACTLY ONE ``.source-chip`` (the bar-clearing doc) and the
+    below-bar docs render only in the de-emphasized ``.related-docs`` row
+    (``.related-doc`` links — never ``.source-chip``), labeled
+    "Nearby docs, in case:". The durable record keeps the FULL retrieval
+    (LOCKED A3)."""
+    _reset_db(mock_llm)
+    page.set_default_timeout(30_000)
+    login(page, app_url, next="/")  # phase 79: chat is require_user-gated
+
+    _ask(page, SINGLE_SOURCE_QUESTION)
+    expect(page.locator(".msg.user .bubble")).to_contain_text(SINGLE_SOURCE_QUESTION)
+
+    bubble = page.locator(".msg.brain .bubble").first
+    bubble.wait_for(state="visible", timeout=30_000)
+    expect(bubble).to_contain_text(MOCK_ANSWER_MARKER, timeout=30_000)
+    # Grounded: no deflected bubble at all.
+    expect(page.locator(".msg.brain.is-deflected")).to_have_count(0)
+
+    # EXACTLY ONE citation chip — the bar-clearing doc (the 2nd chip of
+    # the pre-phase turn demoted to the row; the acceptance criterion).
+    chip = page.locator(".msg.brain .source-chip")
+    expect(chip).to_have_count(1, timeout=30_000)
+    expect(chip.first).to_contain_text("ssh_aliases.txt")
+
+    # The below-bar docs ride the related row: a labeled, de-emphasized
+    # list — one .related-doc link per doc (rank order, capped at
+    # related_max_docs = 2), never a .source-chip.
+    row = page.locator(".msg.brain .related-docs")
+    expect(row).to_have_count(1)
+    expect(row.first).to_have_attribute("aria-label", "Nearby docs, in case")
+    expect(row.first.locator(".related-docs-label")).to_have_text("Nearby docs, in case:")
+    links = page.locator(".msg.brain .related-docs .related-doc")
+    expect(links).to_have_count(2, timeout=30_000)
+    expect(links.nth(0)).to_contain_text("gitlab-compose.yaml")
+    expect(links.nth(1)).to_contain_text("uptime_probe.py")
+    expect(page.locator(".msg.brain .related-docs .source-chip")).to_have_count(0)
+    # The related links keep the chip's /document.html href + identity.
+    expect(links.first).to_have_attribute(
+        "title", "docs/homelab/container_gitlab/gitlab-compose.yaml"
+    )
+
+    # Durable record: not deflected; the FULL retrieval (cited + related)
+    # is logged — query_log records retrieval, not citations (LOCKED A3).
+    with SessionLocal() as db:
+        row_log = db.scalars(select(QueryLog)).one()
+    assert row_log.question == SINGLE_SOURCE_QUESTION
+    assert row_log.deflected is False
+    for path in (
+        "homelab/ssh/ssh_aliases.txt",
+        "homelab/container_gitlab/gitlab-compose.yaml",
+        "homelab/scripts/uptime_probe.py",
+    ):
+        assert path in row_log.sources
+
+
+def test_deflected_question_shows_zero_citation_chips(
+    page: Page, app_url: str, mock_llm: int, db_ready: None
+) -> None:
+    """The acceptance pin: a deflected turn (known-out-of-KB) → ZERO
+    ``.source-chip`` elements under the bubble; the weak hits live in the
+    related row only — its links are ``.related-doc``, never
+    ``.source-chip`` (L2c: "at minimum: never render them as answer
+    citations"). The "Maybe try" chips and the durable record are
+    unchanged."""
+    _reset_db(mock_llm)
+    page.set_default_timeout(30_000)
+    login(page, app_url, next="/")  # phase 79: chat is require_user-gated
+
+    _ask(page, OFF_TOPIC)
+    bubble = page.locator(".msg.brain.is-deflected .bubble").first
+    bubble.wait_for(state="visible", timeout=30_000)
+    expect(page.locator(".msg.brain.is-deflected")).to_have_count(1)
+
+    # Wait for the done frame to have fully rendered (the related row and
+    # the suggestion chips append in it), THEN pin the absence of chips —
+    # a mid-stream reading would be a false zero.
+    chips = page.locator(".msg.brain.is-deflected .maybe-try .suggestion-chip")
+    expect(chips.first).to_be_visible(timeout=30_000)
+    assert chips.count() >= 2, "deflection must offer 2-3 alternative chips"
+
+    row = page.locator(".msg.brain .related-docs")
+    expect(row).to_have_count(1, timeout=30_000)
+    links = page.locator(".msg.brain .related-docs .related-doc")
+    expect(links).to_have_count(2)  # the weak hits, rank order, capped at 2
+    expect(links.nth(0)).to_contain_text("new-service.md")
+    expect(links.nth(1)).to_contain_text("ssh_aliases.txt")
+
+    # ZERO citation chips under the bubble — the weak hits are scored
+    # docs, not citations (the phase-112/113 contract on the wire).
+    expect(page.locator(".msg.brain .source-chip")).to_have_count(0)
+    expect(page.locator(".msg.brain .related-docs .source-chip")).to_have_count(0)
+
+    # Durable record: deflected, weak top score — the retrieval stays
+    # logged for threshold tuning (LOCKED A3: observability unchanged).
+    with SessionLocal() as db:
+        row_log = db.scalars(select(QueryLog)).one()
+    assert row_log.question == OFF_TOPIC
+    assert row_log.deflected is True
+    assert 0.0 < row_log.top_score < get_settings().relevance_threshold
+    assert row_log.fts_hits == 0
+    assert row_log.sources  # the weak-hit paths, for threshold tuning