classify_r3 normalizes the rate reader into a ComprehensionAttempt; route_setup now tries R1/R2/R3 (same exactly-one-setup_correct rule); the pass manager solves+verifies a routed r3_rate setup (solve_rate + reused answer-choice verifier); unsupported_temporal_state dropped from the unsupported-family set so temporal_state -> REFUSED_KNOWN_BOUNDARY. Organ gains r3_rate.
Terminal matrix (verified): 6 solved->SOLVED_VERIFIED; rate_unit_mismatch+combined_rates->PROPOSAL_EMITTED(unsupported_rate_duration); non_integer/missing_time/temporal->REFUSED_KNOWN_BOUNDARY; exactly 2 proposals (the rate-like gaps only).
REGRESSION CAUGHT+FIXED: R3's reader returned missing_rate (a substantive boundary) on non-rate R2 text, blocking r2-011's legitimate missing_total_count proposal via boundary-first. Fix: missing_rate only when a duration is present; else not_rate_shaped -> input_shape (not-my-domain) — same discipline as the N6 category_pair_not_found fix. r2-011 proposes again; R1/R2 unaffected. R1 7/0/3, 15-case 15/0/0, R2 10/0/0, R3 8/0/0 unchanged; off-serving; 121-test smoke green incl. invariants + idle contract suites.
generate/rate_comprehension/solver.py: solve_rate computes the one unknown — quantity=rate×time (always integer), rate=quantity÷time, time=quantity÷rate (exact division or REFUSE non_integer_solution, never rounds). Confirms compound-unit composition via the R3a algebra (defensive; a RateProblem's units compose by construction). answer_unit gives the answer's unit. No floats.
Ties to the gold: solves all 6 solved fixtures to gold; refuses both solver_refuses with non_integer_solution. Meaningful-fail: 100÷3 refuses (not 33), 99÷3=33. Off-serving. 5 tests.
generate/rate_comprehension/units.py: BaseUnit + RateUnit (numerator/denominator) + the three single-rate compositions — rate_times_time (mile/hour × hour = mile; refuses mile/hour × minute), rate_from_quantity_over_time (mile ÷ hour = mile/hour), time_from_quantity_over_rate (mile ÷ mile/hour = hour; refuses dollar ÷ mile/hour). A non-composing op raises UnitError (the wrong=0 dimensional gate), never fabricates a unit.
Deliberately tiny: bare-name units, no generic dimensional universe, no semantic unit-class typing, no unit conversion, no compound-of-compound. Fresh off-serving organ (generate/rate_comprehension/). 10 tests incl. all three refusals + consistent composition.