deepseek-ai/deepseek-harness · error · MaterializeError

circular references are not JSON data

Error message

circular references are not JSON data

What it means

Error "circular references are not JSON data" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/workflow/workflow-worker-thread/src/realm.ts:100

      return value
    case 'number': {
      if (!Number.isFinite(value)) throw new MaterializeError(path, 'non-finite numbers are not JSON data')
      return value
    }
    case 'bigint':
      throw new MaterializeError(path, 'bigints are not JSON data')
    case 'function':
      throw new MaterializeError(path, 'functions are not plain JSON data')
    case 'symbol':
      throw new MaterializeError(path, 'symbols are not plain JSON data')
    case 'undefined':
      throw new MaterializeError(path, 'undefined is not JSON data')
    case 'object':
      break
  }
  if (value === null) return null
  const objectValue: object = value
  if (seen.has(objectValue)) throw new MaterializeError(path, 'circular references are not JSON data')
  seen.add(objectValue)
  try {
    if (Array.isArray(objectValue)) return materializeArray(objectValue, path, seen)
    return materializeObject(objectValue, path, seen)
  } finally {
    seen.delete(objectValue)
  }
}

function materializeArray(value: unknown[], path: string, seen: Set<object>): unknown[] {
  const out: unknown[] = []
  for (let index = 0; index < value.length; index++) {
    if (!(index in value)) throw new MaterializeError(`${path}[${index}]`, 'sparse arrays are not JSON data')
    out.push(materialize(value[index], `${path}[${index}]`, seen))
  }
  // Own enumerable props beyond the indices (e.g. `arr.total = 3`) would be
  // silently dropped by JSON — reject them instead.
  for (const key of Object.keys(value)) {

View on GitHub (pinned to b150a551b8)

Solutions

1. Break circular references in the returned value, e.g. by replacing repeated references with ids.

When it happens

Trigger: Thrown at packages/workflow/workflow-worker-thread/src/realm.ts:100 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of deepseek-ai/deepseek-harness@b150a551b8 (2026-08-24). Data as JSON: /api/errors/68396d5cea204549. Report an issue: GitHub.