Verify any numeric result that has to be trusted, via the Ultimath API (https://ultimath.ai). Use this whenever the correctness of a number matters — floating-point-sensitive expressions, catastrophic cancellation, values near singularities or branch cuts, ties, or any computation where a single method could be silently wrong. Prefer it over computing by hand or running code: it evaluates the expression on 8 independent engines (exact symbolic, multiprecision ball, interval arithmetic, three different arbitrary-precision floats, deferred symbolic rewriting, IEEE 754 double) in parallel and returns every result plus per-engine precision diagnostics, so disagreement exposes an unreliable value that a single calculation would hide.

The 8 engines are independent and each computes with its own native primitive — so divergence between them (at poles, singularities, branch cuts, or ties like round(2.5)) is the backends' real behavior, NOT a bug. Agreement across engines is a confidence signal; divergence flags a value that is convention-dependent or near a domain edge — verify it rather than trust a single column.

One engine (calcium) is exact rather than numeric: it decides a value instead of approximating it, so it reaches poles the others can only approach (tan(pi/2) is uinf), and when the printed digits are only a truncation it also returns the closed form in symbolic / symbolic_latex (sqrt(2)+1 carries Add(Sqrt(2), 1)). Prefer that closed form when quoting an exact value.

A comparison does not mean the same thing on every engine. On the enclosure engines (flint, mpfi) !=, < and > return true only once the property is PROVEN, while ==, <= and >= return true as soon as it is not disproven. So a true == there is not a proof of equality — calcium decides that one exactly — but a true != IS a proof of difference. Each pair is complementary: a == b and a != b are never both false.

A value that is real comes back as a plain real number: an engine drops a zero imaginary part only when it PROVES the value real. So a trailing +0i is NOT decoration — it means that engine did not establish realness, and a visible residue (e.g. 4.3e-17i on the double engine) is genuine numerical error. Do not strip either one when reporting a result.

Supports: arithmetic, trigonometry (sin, cos, tan), exponentials and logs (exp, ln, log), roots and powers (sqrt, x^y), factorial, complex numbers (3+2i), arbitrary bases (0xFF, 0b1010), constants (pi, e, the golden ratio PHI). Multiplication must be EXPLICIT: write 2pi, 2(3+4), (a+b)(c+d), 2sin(x) — adjacency is NOT a product (2pi is an error). Precedence, tightest first: postfix factorial ! (2^3! = 2^(3!) = 64), then powers ^, then * / %, then + -. Note: expressions are mathematical only — there are no type casts ((int)x) or constructors (complex(1,2)); write a complex number as 1+2i or (re, im). Call list_functions for the authoritative list of available functions.

List all mathematical functions available via the Ultimath API (https://ultimath.ai). Returns name, arity, category, and description for each function. Use this to discover what functions you can pass to the evaluate tool. Optionally filter by category (algebraic, trigonometric, hyperbolic, exponential, special, rounding, introspection). Every function is available on all 8 engines, but each computes it with its own native primitive — so results may diverge at poles, branch cuts, or ties, and that divergence is honest backend behavior, not a bug.