grafana/k6 · error

no cookies provided

Error message

no cookies provided

What it means

Validation error from BrowserContext.AddCookies: the cookies argument was an empty array, so the method refuses to make the CDP Storage.setCookies call at all. k6 treats 'add no cookies' as a caller mistake rather than a no-op, matching the strict input validation style of the cookie API.

Source

Thrown at internal/js/modules/k6/browser/common/browser_context.go:460

				out <- p
				return
			}
		}
	}
}

func (b *BrowserContext) getSession(id target.SessionID) *Session {
	return b.browser.conn.getSession(id)
}

// AddCookies adds cookies into this browser context.
// All pages within this context will have these cookies installed.
func (b *BrowserContext) AddCookies(cookies []*Cookie) error {
	b.logger.Debugf("BrowserContext:AddCookies", "bctxid:%v", b.id)

	// skip work if no cookies provided.
	if len(cookies) == 0 {
		return fmt.Errorf("no cookies provided")
	}

	cookiesToSet := make([]*network.CookieParam, 0, len(cookies))
	for _, c := range cookies {
		if c.Name == "" {
			return fmt.Errorf("cookie name must be set: %#v", c)
		}
		if c.Value == "" {
			return fmt.Errorf("cookie value must be set: %#v", c)
		}
		// if URL is not set, both Domain and Path must be provided
		if c.URL == "" && (c.Domain == "" || c.Path == "") {
			const msg = "if cookie URL is not provided, both domain and path must be specified: %#v"
			return fmt.Errorf(msg, c)
		}
		// calculate the cookie expiration date, session cookie if not set.
		var ts *cdp.TimeSinceEpoch
		if c.Expires > 0 {

View on GitHub (pinned to 93accf6570)

Solutions

1. Skip the call when the list is empty: if (cookies.length) context.addCookies(cookies).
2. If you expected cookies, debug why the array is empty (check the parsing/fixture code that populates it) before calling addCookies.
3. Ensure each cookie object has at least name and value plus url or domain+path.

Example fix

// before
context.addCookies(cookiesFromLogin); // empty at runtime

// after
if (cookiesFromLogin.length > 0) {
  context.addCookies(cookiesFromLogin);
}

if (!Array.isArray(cookies) || cookies.length === 0) {
  // nothing to install; skip the call (k6 rejects empty arrays)
} else {
  context.addCookies(cookies);
}

When it happens

Trigger: Calling browserContext.addCookies([]) with a literal empty array, or with a variable that is empty at runtime (e.g. parsed from a file or built in a loop that matched nothing).

Common situations: Dynamically building a cookie list from shared state, an HTTP response, or a JSON fixture that turns out empty; refactoring that leaves a placeholder addCookies([]) call; passing cookies to the wrong context before they are set.

Related errors

• cookie name must be set: %#v
• cookie value must be set: %#v
• if cookie URL is not provided, both domain and path must be
• filtering cookies: %w
• parsing urls: %w

AI-assisted analysis of grafana/k6@93accf6570 (2026-08-15). Data as JSON: /api/errors/42c102eeda750460. Report an issue: GitHub.