# Phase 26 — UPS events: power events collapsible, connection errors always visible

**Source:** `TODO.md` L6 — "The phase I ran earlier collapsed all the events in the UPS tab. That wasn't the point. I wanted the power loss events in a collapsible list, not events like \"NUT server NutError: cannot reach upsd at 10.1.0.126:3051 (timed out after 4s)\" in a collapsible list."
**Story:** n/a
**Context:** phase 19 (complete) put the **whole** `/ups` event feed behind one collapsed `details.events-box` (no `open` attribute, lazy: `refresh()` fetches the feed only while `state.events.open`, the first expand fetches, a fresh re-expand paints from the `<ul>`'s kept children, `painted`/`fetchedAt` stamped on the success path alone, the `Dash.eventsPager` window of 50 inside the bounded 320px scroll). The operator's complaint is that the classification is wrong, not that a collapse exists: a poll failure like `NUT server NutError: cannot reach upsd … (timed out after 4s)` is hidden behind a summary nobody opens, while the power events it was meant to tuck away are the only ones the operator actually wants collapsed. The feed's **kinds** are fixed and known: the poller (`collectors.py:490` — `Job("nut", "ups", "NUT server", …)`, events under the dashboard name `ups`) writes `unreachable` / `reachable` / `recording` / `store-error` (`poller.py:127/157/164/190` — the quoted `NutError` line is the `unreachable` message); the `NutMonitor` transition bookkeeping writes `status` (a state change lands at `collectors.py:393`) and `test` (the self-test verdict, `collectors.py:409`); `api.py` writes `action` for every command sent through `POST /api/ups/command` (the fixed-text `action` events, `api.py:999/1014`). The served-byte pins for the current shape are in `tests/test_api.py`: `test_ups_power_events_feed_sits_behind_a_collapsed_disclosure` (the `details.events-box`, no `open`, `#events` inside), `test_ups_events_are_fetched_only_while_the_disclosure_is_open` (the lazy gate — **this phase inverts it on purpose**), `test_the_ups_event_rows_keep_the_date_time_and_severity_shape` (the row shape), `test_the_ups_events_disclosure_is_a_quiet_disclosure_not_a_new_component` (the `details.events-box` CSS shape — unchanged by this phase). The page is `src/dashboards/web/static/page-ups.js` (`refresh()` around line 439, `refreshEvents()` around line 445, the disclosure's toggle handler in the `DOMContentLoaded` block) over the card in `src/dashboards/web/pages/ups.html:75-78`.

## Objective

`/ups` renders **two** lists from the one unchanged feed fetch: the power events — state transitions (including the power-loss transitions), self-test verdicts and sent commands — stay behind the collapsed `details.events-box` disclosure, and the connection/error events (`unreachable`/`reachable`/`recording`/`store-error`) are a card that is **always visible** (hidden only while it has no rows to show). The split is page-side, keyed on the event's `kind`; `/api/events` gains no vocabulary.

## Dependencies
- — (none) — the phase builds on complete phase 19; it is scheduled before `27_mobile_tables_and_audit` on purpose, because that phase's mobile audit captures `/ups` in the shape this phase leaves it in (two cards, one of them hidden-when-empty).

## Tasks
1. `01_page_side_event_split.md` — the `kind` split in `page-ups.js` (power kinds `status`/`test`/`action`, everything else errors) and the removal of the phase-19 lazy gate: the feed is fetched on every poll, because a visible list that ages is worse than one more 200-event fetch per interval
2. `02_render_both_lists_paged.md` — the always-visible `#events-errors` card (above the disclosure, hidden while empty) and both lists paged through the shared `Dash.eventsPager`
3. `03_repin_and_browser_verify.md` — the pin re-pins (the disclosure stays, the lazy gate inverts, the row shape extends to the error list, the kind set is pinned so a silent upstream rename breaks a test) and the phase's real-browser verification

## Testing & Quality
- Unit/integration: the re-pinned and new pins in `tests/test_api.py` (task 03); the split itself is pinned on the served script (the kind set) and the served markup (the error card, `hidden`, not inside a `<details>`)
- Coverage: **>90%** on new/modified code
- Real-browser check (invariant 10): a `data/logs/26-task03-*.cjs` script in the `20-task01-rows.cjs` convention, run against the restarted dev server: the disclosure shut by default, the error card's visibility matching the feed's error-kind rows, both lists' rows matching a direct `/api/events?source=ups&limit=200` split, screenshots in `data/logs/`

## Documentation & Consistency

- The final pass updates the now-stale sentences in `AGENTS.md`: the event-feed paragraph's lazy-fetch block ("`refresh()` fetches the feed only while `state.events.open` is true, so a card nobody is looking at costs the poll loop nothing" and the first-expand/fresh-re-expand sentences) is re-written to the new fact (the one fetch serves two lists, always; the disclosure gates only the power list's visibility), and the pin description of `test_ups_events_are_fetched_only_while_the_disclosure_is_open` is re-pointed at its inverted successor. `README.md` is checked for the same sentence; none is expected.

## Completion Criteria
- [ ] a poll failure (e.g. `NUT server NutError: cannot reach upsd …`) is visible on `/ups` without opening anything, and the power events stay behind the collapsed disclosure (pinned + verified in a browser)
- [ ] the error card is hidden while it has no rows and appears with its first error row; both lists share the one `/api/events?source=ups` fetch and the shared pager (pinned)
- [ ] a failed fetch leaves both lists on their last good rows (the stale-last-good rule) — pinned where phase 19 pinned its
- [ ] `uv run pytest` green, coverage not down, `ruff` + `pyright` clean
- [ ] `bash .agents/validate.sh` green
- [ ] no behavior change in completed work: the `details.events-box` CSS shape, the pager's page/scroll semantics, and the row's time/host/severity shape are untouched