different-ai/openwork · error · InterpreterRuntimeError

Object.fromEntries expects [key, value] pairs.

Error message

Object.fromEntries expects [key, value] pairs.

What it means

After confirming the fromEntries argument is an array, CodeMode validates each element is itself an array ([key, value] pair). A non-array element throws this second, more specific message.

Source

Thrown at packages/codemode/src/stdlib/object.ts:69

    case "fromEntries": {
      if (args[0] instanceof SandboxMap) {
        const out: Record<string, unknown> = Object.create(null)
        for (const [key, item] of args[0].map.entries()) guardedSet(out, coerceToString(key), item)
        return out
      }
      if (args[0] instanceof SandboxURLSearchParams) {
        const out: Record<string, unknown> = Object.create(null)
        for (const [key, value] of args[0].params.entries()) guardedSet(out, key, value)
        return out
      }
      const pairs = boundedData(args[0], "Object.fromEntries input")
      if (!Array.isArray(pairs)) {
        throw new InterpreterRuntimeError("Object.fromEntries expects an array of [key, value] pairs.", node)
      }
      const out: Record<string, unknown> = Object.create(null)
      for (const pair of pairs) {
        if (!Array.isArray(pair)) {
          throw new InterpreterRuntimeError("Object.fromEntries expects [key, value] pairs.", node)
        }
        guardedSet(out, String(pair[0]), pair[1])
      }
      return out
    }
  }
  throw new InterpreterRuntimeError(`Object.${name} is not available in CodeMode.`, node)
}

View on GitHub (pinned to 2b7df46e8a)

Solutions

1. Ensure each element is a 2-tuple: pairs.map(p => Array.isArray(p) ? p : [p.key, p.value])
2. If you only have keys, build pairs: Object.keys(o).map(k => [k, o[k]])
3. Filter malformed rows first: pairs.filter(p => Array.isArray(p) && p.length >= 2)
4. Convert {key,value} object rows with rows.map(r => [r.key, r.value])

Example fix

// before
const record = Object.fromEntries(rows)
// after
const record = Object.fromEntries(rows.map(r => [r.key, r.value]))

const isPair = (p: unknown): p is [string, unknown] => Array.isArray(p) && p.length >= 2
const safePairs = raw.filter(isPair)
const record = Object.fromEntries(safePairs)

const isPair = (p: unknown): p is [unknown, unknown] => Array.isArray(p)

try {
  return Object.fromEntries(pairs)
} catch (e) {
  if (e instanceof InterpreterRuntimeError && e.message.includes('expects [key, value] pairs')) {
    return Object.fromEntries(pairs.filter((p) => Array.isArray(p)))
  }
  throw e
}

When it happens

Trigger: Object.fromEntries(['ab', 'cd']) (strings not split into pairs), Object.fromEntries([{key:'a', value:1}]) (objects instead of tuples), Object.fromEntries(Object.keys(o)) forgetting values, pairs built with nulls in between.

Common situations: Hand-building pair arrays where one row was a string due to a split() miss; schema drift from an API returning {key,value} objects; filtering that left a null hole in the pairs array.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• Object.${name} expects a data object.
• Object.keys expects a data object or array.
• Object.assign expects data objects.
• Object.fromEntries expects an array of [key, value] pairs.
• String.${name} expects argument ${index + 1} to be a number.

AI-assisted analysis of different-ai/openwork@2b7df46e8a (2026-09-01). Data as JSON: /api/errors/3e81a86fd956ddb4. Report an issue: GitHub.