different-ai/openwork · error · InterpreterRuntimeError

Math.${name} expects number arguments.

Error message

Math.${name} expects number arguments.

What it means

Once the method name passes the whitelist check, CodeMode validates that every argument is a number. Non-numeric arguments (strings, NaN-producing values from upstream, undefined) are rejected with this error instead of being silently coerced, keeping sandbox math strict and predictable.

Source

Thrown at packages/codemode/src/stdlib/math.ts:25

  "floor",
  "ceil",
  "round",
  "trunc",
  "sign",
  "sqrt",
  "cbrt",
  "pow",
  "hypot",
  "log",
  "log2",
  "log10",
  "exp",
])

export const invokeMathMethod = (name: string, args: Array<unknown>, node: AstNode): number => {
  if (!mathMethods.has(name)) throw new InterpreterRuntimeError(`Math.${name} is not available in CodeMode.`, node)
  const nums = args.map((arg) => {
    if (typeof arg !== "number") throw new InterpreterRuntimeError(`Math.${name} expects number arguments.`, node)
    return arg
  })
  const [a = Number.NaN, b = Number.NaN] = nums
  switch (name) {
    case "max":
      return Math.max(...nums)
    case "min":
      return Math.min(...nums)
    case "abs":
      return Math.abs(a)
    case "floor":
      return Math.floor(a)
    case "ceil":
      return Math.ceil(a)
    case "round":
      return Math.round(a)
    case "trunc":
      return Math.trunc(a)

View on GitHub (pinned to 2b7df46e8a)

Solutions

1. Coerce inputs explicitly with Number(x) before passing them to Math methods.
2. Filter the array before spreading: nums.filter(n => typeof n === "number").
3. Guard optional/missing values with a default before the call.

Example fix

// before
const m = Math.max(...values)
// after
const m = Math.max(...values.filter((n) => typeof n === "number"))

const nums = args.filter((a) => typeof a === "number")
if (nums.length !== args.length) throw new TypeError("Math arguments must all be numbers")

const isNum = (v: unknown): v is number => typeof v === "number" && Number.isFinite(v)

try { return Math.max(...values) } catch (e) { if (/expects number arguments/.test(String(e))) return Math.max(...values.filter(isNum)); throw e }

When it happens

Trigger: Calling any supported Math method with a non-number argument: Math.pow("2", 3), Math.max(...arr) where arr contains undefined, Math.log2(values[0]) where the array slot is missing.

Common situations: Spreading arrays that may contain holes or undefined entries (Math.max(...sparse)); passing numeric strings from JSON input without Number() conversion; downstream functions returning undefined on edge cases.

Related errors

• String.${name} expects argument ${index + 1} to be a number.
• JSON.parse expects a string.
• Number.${name} expects a number argument.
• Number.parseInt expects a numeric radix.
• Object.${name} expects a data object.

AI-assisted analysis of different-ai/openwork@2b7df46e8a (2026-09-01). Data as JSON: /api/errors/ebfaae0ef06e5ee0. Report an issue: GitHub.