# Phase 36 — Document Summary Shown Together With the Original

**Source:** `TODO.md` L5 — "When I click on a document with a summary I should be able to see the summary and the original document together."
**Story:** `.agent/user_stories/summary-in-viewer.md`
**Context:** Phase 30 stores a lite-model summary on `documents.summary` for every non-markdown document (plus an indexed `is_summary` chunk) — but the viewer never shows it: `GET /api/documents/content` omits the field and the shared renderer `renderDocument` (`frontend/assets/document.js`, used by BOTH the full-page viewer `document.html` and the chat/sources modal, phase 26) only renders the raw content. Markdown documents carry no summary (phase 30) and must render exactly as before.

## Objective
When a document **has** a summary, show it and the original content together — a labeled Summary panel above the content, on both viewer surfaces at once (shared renderer); documents without a summary are unchanged.

## Dependencies
- `30_document_summaries` (complete) — the `documents.summary` column (migration 0004), the summarizer, the `summary_kb` E2E fixture + the deterministic mock `SUMMARY_MODE` digest.
- `10_story_document_viewer` + `26_document_modal_viewer` (complete) — the viewer page, the modal, and the shared `renderDocument(doc, {titleEl, metaEl, contentEl})` core both surfaces render through.
- `16_admin_auth` (complete) — the soft rule this phase must not touch: the content endpoint stays public + stateless (catalog gated, viewer public).

## Tasks
1. `01_content_api_summary_field.md` — `DocContent.summary` + the endpoint returns it; integration tests.
2. `02_viewer_summary_panel.md` — the shared renderer draws the `.doc-summary` panel (both surfaces) + theme-matched styles.
3. `03_e2e_and_regression.md` — the story E2E suite `test_summary_in_viewer.py`; regressions; full gate; commit.

## Testing & Quality
- Unit/integration: the content endpoint returns the summary for a summarized non-markdown doc and `null` for a markdown doc; anonymous access unchanged.
- Coverage: **>90%** on `app/` (the touched endpoint stays covered).
- E2E (mandatory, A16): `tests/e2e/test_summary_in_viewer.py` — the story gate, run in isolation.

## Completion Criteria
- [ ] `GET /api/documents/content` returns `summary` (string or null); no auth/shape change beyond the added nullable field; the endpoint is still public.
- [ ] A summarized document shows the labeled Summary panel **above** the original content in the full-page viewer AND the modal; the original content (including content the summary digest doesn't contain) is fully visible.
- [ ] A markdown document (no summary) renders exactly as before on both surfaces — no empty panel.
- [ ] `uv run pytest` green; `uv run pytest --cov=app --cov-report=term-missing` >90%; `uv run pytest tests/e2e/test_summary_in_viewer.py -v --no-cov` green in isolation; regressions (task 03 list) green.
- [ ] `uv run ruff check . && uv run pyright` clean.
- [ ] UI Structure Check (AGENTS.md rule 5): the panel is a labeled section, contrast ≥4.5:1, no CDN (rule 6).
- [ ] One `--no-gpg-sign` commit; phase directory moved to `.agent/phases/complete/`.

## Locked decisions
- **A7 / A15 untouched** — retrieval, context assembly, and the SSE contract are unchanged; this is a display + API-field phase.
- **Phase 16 soft rule untouched** — `GET /api/documents/content` stays public + stateless (anyone who can open a document sees its summary; the catalog stays admin-gated).
- **Phase 30 untouched** — summaries are still generated at import, still markdown-excluded, still fail-soft (NULL possible); this phase only surfaces the existing field.
- **Shared-renderer principle (phase 26)** — the panel is drawn in `renderDocument`, so the page and the modal can never drift.
- **A11 untouched** — vanilla HTML/CSS/JS, no CDN, no new packages; summary text rendered with `textContent` (XSS contract unchanged).
- **A16 / A17 honoured** — one new story E2E suite + one atomic `--no-gpg-sign` commit.