phase: 117_tool_call_compact

All verification complete — every gate green. Final report:

**Phase 117 final verification pass — all criteria verified** (tasks 01–04 were already in `complete/`; I re-verified the full gate myself, no code changes needed)
- **Verified:** `appendToolLine` wraps lines in `details.tool-calls-disclosure` (open live, `closeToolCalls` at delta/done/stop + restore-closed, count via textContent); `addToolLines` parity (closed); `.tool-call` deboxed / `code` dechipped; new disclosure/summary CSS; only the one pinned CSS assert updated
- `uv run pytest` → **2466 passed**
- `uv run pytest --cov=app --cov-report=term-missing` → **99%** on `app/` (>90% floor)
- E2E in isolation: `test_tool_call_compact.py` **4 passed** (fold/expand/deboxed-flow/restored-folded); `test_agent_document_tools.py` **4 passed**; `test_big_read_progress.py` **4 passed** (live disclosure open + `.tool-elapsed` visible); `test_thinking_display.py` **5 passed**; `test_smoke.py` **3 passed**
- `uv run ruff check . && uv run pyright` → clean (pyright 0 errors, 0 warnings)
- Completion criteria: pins 1–4 ✅ (E2E above); live "calling tool" state byte-identical ✅ (`test_frontend_tool_states.py` 10 passed incl. `test_calling_tool_label_strings`); scope ✅ — `git diff` limited to the 3 frontend assets + 2 unit tests + E2E story + phase files, **0 changes in `app/`**
- Notable: `TODO.md` carries a **pre-existing uncommitted owner edit** (new retrieval-context idea) already in the tree before this pass — left untouched, will ride along in the harness commit; pre-existing committed quirk: the brain-wave commit's styles.css comment mislabels itself "Phase 117" (cosmetic, out of this diff)
- No commit made (harness commits + moves the phase); **next pending phase: none** — `todo/` holds only phase 117

frontend/assets/styles.css

@@ -615,42 +615,74 @@ details.thinking .thinking-text {
 details.thinking .thinking-text p,
 details.thinking .thinking-text ul { margin: 0 0 0.5rem; }
 
-/* Agent tool-call lines (phase 37): one visible "calling tool" row per
-   `tool` SSE frame — in the same wrap as the Thinking block, above the
-   answer, below the Thinking summary. Deliberately distinct from the
-   scratchpad: accent palette (--accent-ink) vs the brand-ink summary,
-   own icon, own accent left border. Contrast: --accent-ink on the row's
-   --surface ≈10.4:1 (11.6:1 on the page bg), and --ink on --brand-soft
-   in the path `code` ≈11.5:1 — all comfortably AA in the (single dark)
-   theme. Inline rows only: appending lines never shifts the chat
-   column (72rem — the .container width at every viewport; no new
-   container), and the rows are not interactive — no focus targets. */
+/* Phase 117: the tool-call record folds into a single disclosure line,
+   reusing the Thinking block's native <details> convention. Open while
+   the turn is live (phase 87's elapsed suffix stays visible), folded at
+   rest / on restore. The summary is a native focusable toggle — it
+   inherits the house 3px :focus-visible ring (see details.thinking
+   summary). Accent rides the TEXT (var(--accent-ink), ≈10.4:1 on the
+   surface) — text + color, never color alone (B5). No new literal. The
+   chevron matches details.thinking summary::before so the two
+   disclosures read as one family — the count text is the accessible
+   label either way. */
+.tool-calls-disclosure { margin: 0.25rem 0; }
+.tool-calls-summary {
+  cursor: pointer;
+  color: var(--accent-ink);
+  font-size: 0.8rem;
+  line-height: 1.4;
+  padding: 0.15rem 0;
+  list-style: none; /* the native marker is redundant with the count text */
+}
+.tool-calls-summary::-webkit-details-marker { display: none; }
+/* CSS chevron: ▸ rotates 90° when open — the same family treatment as
+   details.thinking summary::before (the transition stills under
+   prefers-reduced-motion — see the reduced-motion block below). */
+.tool-calls-summary::before {
+  content: "▸";
+  display: inline-block;
+  margin-right: 0.5rem;
+  transition: transform 0.15s ease;
+}
+.tool-calls-disclosure[open] .tool-calls-summary::before {
+  transform: rotate(90deg);
+}
+
+/* Agent tool-call lines (phase 37, deboxed in phase 117): one compact
+   inline-flow row per `tool` SSE frame — in the same wrap as the
+   Thinking block, above the answer, below the Thinking summary, inside
+   the phase-117 disclosure. Deliberately distinct from the scratchpad:
+   accent text (--accent-ink) vs the brand-ink summary. Contrast:
+   --accent-ink on the surface ≈10.4:1 (11.6:1 on the page bg), and
+   --ink on the surface in the path `code` ≈11.5:1 — all comfortably AA
+   in the (single dark) theme. Inline rows only: appending lines never
+   shifts the chat column (72rem — the .container width at every
+   viewport; no new container), and the rows are not interactive — no
+   focus targets (the fold is the disclosure's native summary). */
 .tool-calls {
   display: flex;
   flex-direction: column;
   gap: 0.25rem;
 }
+/* Phase 117 deboxed the line (owner visual-glitch report 2026-09-15):
+   no card, no flex — the label + the inline `code` flow as ONE
+   continuous run, so a long path wraps to the left edge like a normal
+   sentence and the label no longer breaks mid-word ("Rea/ding" is
+   gone). The accent now rides the TEXT color (var(--accent-ink))
+   instead of a border. */
 .tool-call {
-  display: flex;
-  align-items: baseline;
-  gap: 0.45rem;
-  background: var(--surface);
-  border: 1px solid var(--line);
-  border-left: 3px solid var(--accent-line);
-  border-radius: var(--radius-sm);
-  padding: 0.3rem 0.75rem;
   color: var(--accent-ink);
   font-size: 0.8rem;
   line-height: 1.4;
   overflow-wrap: anywhere;
 }
+/* Phase 117 dechipped the path: it keeps the mono + ink treatment
+   (var(--ink) on the surface ≈11.5:1 — AA) but loses the chip
+   background — it is inline text in the line's run now. */
 .tool-call code {
   font-family: var(--mono);
   font-size: 0.95em;
-  background: var(--brand-soft);
   color: var(--ink);
-  padding: 0.05em 0.35em;
-  border-radius: 5px;
   overflow-wrap: anywhere;
 }
 /* Phase 87 (TODO.md L5): the latest tool line's visible "processing"
@@ -1253,6 +1285,8 @@ details.thinking .thinking-text ul { margin: 0 0 0.5rem; }
   .typing span.typing-elapsed { opacity: 1; }
   /* Phase 17 thinking block: the chevron stills (no rotation motion). */
   details.thinking summary::before { transition: none; }
+  /* Phase 117 tool-calls disclosure: the same chevron, the same still. */
+  .tool-calls-summary::before { transition: none; }
 }
 
 /* Phase 117 (owner request 2026-09-15, live-mockup-confirmed — the