phase: 160_tool_budget_telemetry

All green. Final report:

**Phase 160 completion pass — verified (final verification; all 5 tasks already in `complete/`)**

- **Verified, no code defects found:** budget trailers (`TOOL_BUDGET_REMAINING/LAST/SPENT`), cap-path rejection + `ROUND_CAP_FALLBACK_ANSWER` + `ROUND_CAP_WRAPUP_INSTRUCTION`, `done.budget_exhausted` (ABSENT-when-false), `rounds=/cap_hit=` log fields, `agent_max_rounds=10` default, frontend Continue button + restore + shared-page exclusion, mock markers.
- **Tests/lint:** `uv run pytest` 153/153 green (EXIT 0); `uv run pytest --cov=app --cov-report=term-missing` TOTAL **99%** (>90%); `uv run ruff check .` clean; `uv run pyright` 0 errors/0 warnings.
- **Criteria:** ① decreasing trailer pinned by unit tests (9→…→spent) ✅ ② cap path ends readable, no tool lines after cap (E2E) ✅ ③ `budget_exhausted` true-only-on-cap, absent otherwise (integration) ✅ ④ Continue button → one fresh `continue` turn, fresh budget, record intact (E2E) ✅ ⑤ flag survives refresh; shared chat never renders it (`shared.js` has no `budget_exhausted` path) ✅ ⑥ `max_rounds=0` byte-identical single `tools=None` request; default still 10 ✅ ⑦ full suite/coverage/lint green ✅ ⑧ `test_tool_budget_telemetry.py` **7/7** in isolation; all 6 regression E2E suites green in isolation ✅ ⑨ commit + phase move = harness (I make no git history/index changes).
- **Docs:** README.md — fixed: the "Continue researching" button and cap behavior were undocumented (added a Chat-section paragraph + an Agent-tools-section paragraph, incl. the phase-71 recorded-revision note); env-var table, commands, and architecture all verified consistent otherwise. AGENTS.md — verified consistent, no changes needed.
- **Decisions:** no code changes required — phase was fully implemented; only README docs added. No live-infrastructure touched.
- **Next pending phase:** `161_reasoning_bubble`.

frontend/assets/styles.css

@@ -1027,6 +1027,39 @@ a.answer-image:hover { text-decoration: underline; } /* flat — the caption und
 .retry-btn svg { width: 14px; height: 14px; display: block; }
 .retry-btn:hover { background: var(--brand-soft); color: var(--ink); }
 
+/* Phase 160 (task 04, TODO L4): the "Continue researching" button —
+   the one-click continuation in the actions row
+   (.msg-meta.msg-actions — phase 130) of a cap-reached brain bubble
+   (the done frame's budget_exhausted, task 03). The exact visual
+   family of .retry-btn (same pill size/spacing, the global
+   :focus-visible ring, >=44px via min-height) so the meta actions
+   read as a set — but neutral: ink-soft -> ink on hover (Tune keeps
+   the brand pair). The forward glyph rides currentColor. No
+   per-button auto margin (phase 130 — the row's justify right-aligns
+   the cluster). No animation of its own, so the
+   prefers-reduced-motion blocks need nothing for it (the family's
+   parity — .retry-btn / .edit-btn have none either). Contrast: ink-soft on --bg ~8.6:1, ink
+   ~15:1, hover ink on --brand-soft ~15.7:1 — all AA. */
+.continue-btn {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  gap: 0.35rem;
+  min-height: 44px;
+  padding: 0.35rem 0.8rem;
+  border-radius: 999px;
+  border: 1px solid var(--line);
+  background: transparent;
+  color: var(--ink-soft);
+  font: inherit;
+  font-weight: 600;
+  font-size: 0.82rem;
+  white-space: nowrap;
+  cursor: pointer;
+}
+.continue-btn svg { width: 14px; height: 14px; display: block; }
+.continue-btn:hover { background: var(--brand-soft); color: var(--ink); }
+
 /* Phase 159 (task 01, TODO L3): the "Edit" button — the
  * trim-and-re-ask action in the .msg-meta.msg-actions row (phase 130)
  * of the NEWEST user bubble (markLastEditable — the phase-49
@@ -5817,6 +5850,7 @@ a.answer-image:hover { text-decoration: underline; } /* flat — the caption und
   .tune-btn { min-height: 44px; }
   .retry-btn { min-height: 44px; }
   .edit-btn { min-height: 44px; }
+  .continue-btn { min-height: 44px; }
   /* Phase 27: the tuning page squeezes like the other cards — the row
      padding tightens; the icon+label actions keep their 44px floor and
      the note text ellipsizes (min-width: 0). */