diff --git a/plans/agent-briefings/primitives-loop.md b/plans/agent-briefings/primitives-loop.md
index f6a5a67b..70c0a7b1 100644
--- a/plans/agent-briefings/primitives-loop.md
+++ b/plans/agent-briefings/primitives-loop.md
@@ -91,7 +91,10 @@ Steps:
 - [x] Spec: update `spec/primitives.sx` with new predicates + coercions; document contagion rules.
       Added integer?/float? predicates; updated number? body; / returns "float"; floor/ceil/truncate
       return "integer"; +/-/* doc float contagion; fixed double-paren params; 4874/394 baseline.
-- [ ] JS bootstrapper: update number representation and arithmetic.
+- [x] JS bootstrapper: update number representation and arithmetic.
+      Added integer?/float?/exact?/inexact?/truncate/remainder/modulo/random-int/exact->inexact/
+      inexact->exact/parse-number. Fixed sx_server.ml epoch protocol for Integer type.
+      JS: 1940 passed (+60); OCaml: 4874/394 unchanged. 6 tests JS-only fail (float≡int limitation).
 - [x] Tests: 92 tests in `spec/tests/test-numeric-tower.sx` — int-arithmetic, float-contagion,
       division, predicates, coercions, rounding, parse-number, equality, modulo, min-max, stringify.
 - [ ] Verify: full suite passes. Pay attention to any test that relied on `1.0 = 1`.
@@ -658,6 +661,7 @@ Brief each language's loop agent (or do inline) after rebasing their branch onto
 
 _Newest first._
 
+- 2026-04-26: Phase 2 JS bootstrapper done — integer?/float?/exact?/inexact? added (Number.isInteger); truncate/remainder/modulo/random-int/exact->inexact/inexact->exact/parse-number added. Fixed sx_server.ml epoch+blob+io-response protocol for Integer type. JS: 1940/2500 (+60). OCaml: 4874/394 baseline. 6 JS tests fail (JS float≡int platform limit). Committed b12a22e6.
 - 2026-04-26: Phase 2 Spec done — integer?/float? predicates added to spec/primitives.sx; floor/ceil/truncate :returns updated to "integer"; / to "float"; exact->inexact/inexact->exact docs and returns updated; float contagion documented on +/-/*; 4874/394 baseline. Committed 45ec5535.
 - 2026-04-26: Phase 2 OCaml+Tests done — `Integer of int` / `Number of float` in sx_types.ml; float contagion across all arithmetic; floor/truncate/round → Integer; integer?/float?/exact?/inexact?/exact->inexact/inexact->exact; 92/92 numeric tower tests pass; 4874 total (394 pre-existing unchanged). Committed c70bbdeb.
 - 2026-04-26: Phase 1 complete — JS step done. Fixed fundamental lambda binding bug (index-of on arrays returned -1 not NIL, making bind-lambda-params mis-fire &rest branch). Added _lastErrorKont_/hostError/try-catch stubs. 42/42 vector tests pass. 1847 std / 2362 full passing (up from 5). Committed.