SeleniumHQ/selenium · error · Error

Status must be an integer. Received:'${statusCode}'

Error message

Status must be an integer. Received:'${statusCode}'

What it means

Thrown by ProvideResponseParameters.statusCode() when the statusCode argument is not an integer (fails Number.isInteger). The BiDi response status must be an integer HTTP status code, so floats, strings, NaN, null, or non-numeric values are rejected before serialization.

Source

Thrown at javascript/selenium-webdriver/bidi/provideResponseParameters.js:111

   */
  reasonPhrase(reasonPhrase) {
    if (typeof reasonPhrase !== 'string') {
      throw new Error(`Reason phrase must be a string. Received: '${reasonPhrase})'`)
    }
    this.#map.set('reasonPhrase', reasonPhrase)
    return this
  }

  /**
   * Sets the status code for the response.
   *
   * @param {number} statusCode - The status code to set.
   * @returns {ProvideResponseParameters} - Returns the ProvideResponseParameters object for chaining.
   * @throws {Error} - If the status code is not an integer.
   */
  statusCode(statusCode) {
    if (!Number.isInteger(statusCode)) {
      throw new Error(`Status must be an integer. Received:'${statusCode}'`)
    }

    this.#map.set('statusCode', statusCode)
    return this
  }

  asMap() {
    return this.#map
  }
}

module.exports = { ProvideResponseParameters }

View on GitHub (pinned to aa36b38e69)

Solutions

1. Pass a plain integer, e.g. params.statusCode(200).
2. If the value comes from a string source, parse and validate: const code = Number.parseInt(raw, 10); if (Number.isInteger(code)) params.statusCode(code).
3. Avoid floats and strings; ensure the value is a JS number with no fractional part.

Example fix

// before
const params = new ProvideResponseParameters(id).statusCode('200')

// after
const params = new ProvideResponseParameters(id).statusCode(200)

if (!Number.isInteger(statusCode)) {
  throw new TypeError('statusCode must be an integer')
}

function isHttpStatusCode(v) {
  return Number.isInteger(v) && v >= 100 && v <= 599
}

When it happens

Trigger: Calling params.statusCode('200') (string), params.statusCode(200.5) (float), params.statusCode(null), params.statusCode(NaN), or params.statusCode(true).

Common situations: Reading the status from a header/config string and not coercing; passing a float computed from a formula; using a BigInt or boolean where a number is expected.

Related errors

• Params must be an instance of ProvideResponseParameters. Rec
• Value must be an instance of BytesValue. Received: ${typeof
• CookieHeader must be an instance of Header. Received:'${head
• Header must be an instance of Header. Received:'${header}'
• Reason phrase must be a string. Received: '${reasonPhrase})'

AI-assisted analysis of SeleniumHQ/selenium@aa36b38e69 (2026-08-14). Data as JSON: /api/errors/6fc90e72f23a8843. Report an issue: GitHub.