playwright proxy server returned 407 proxy authentication required per context

TL;DR

The 407 means the proxy wants credentials and is not getting them. In Playwright, proxy auth belongs on the browser or context proxy options (username and password fields), and per-context auth means passing a different proxy object per new_context, not per page. Verify with the requestfailed failure detail, and keep secrets out of code by reading them from the environment.

playwright proxy server returned 407 proxy authentication required per context

Use this when

• Playwright navigations fail with 407 while curl through the same proxy works.
• Each context needs different proxy credentials.
• The proxy requires auth on CONNECT.

Not for this skill when

• The 401/403 comes from the target site. That is origin auth, not proxy auth.
• The proxy uses Kerberos/NTLM. Playwright cannot do that handshake natively.

Steps

1. Pass credentials in the proxy object: new_context(proxy={"server": "https://example.com", "username": USER, "password": PASS}) with USER and PASS read from environment variables. Verify: the 407 clears on the next navigation.
2. For per-context creds, create one context per credential set. Do not try per-page proxy auth; Playwright scopes proxy config to browser and context. Verify: two contexts with different creds both authenticate.
3. Confirm the failure is proxy-side: listen on requestfailed and log failure(). Verify: the message names proxy authentication, not the target.
4. Test the same credentials with curl through the proxy first. Verify: curl succeeds, proving the creds are good and the problem is Playwright-side wiring.
5. If 407 persists with correct creds, check the proxy scheme: some proxies need the https scheme server URLs or a specific port. Verify: matching curl's exact server string fixes it.

Variant phrasings

playwright 407 proxy auth

The short search, same credential-placement fix.

playwright proxy username password not working

Wiring phrasing, points at step 1.

per context proxy authentication playwright

Scope phrasing, answered in step 2.

Compatibility: Playwright 1.x. Proxy config is per browser/context, never per page or per request.

Why it happens

A 407 is the proxy's challenge for credentials, and Playwright only sends them when they are part of the proxy configuration object. People often set the server but forget the fields, or set them on the browser launch and expect per-context override to merge. The proxy then sees an unauthenticated CONNECT and answers 407.

Edge cases / pitfalls

• Never hard-code proxy credentials in the script. Environment variables or a secrets manager; the script gets committed, the secrets do not.
• Rotating credentials per request is not supported. One credential set per context.
• Some proxies 407 on HTTP but not HTTPS targets (or vice versa). Test both schemes.
• A 407 that appears mid-session usually means the credential expired. Refresh the context, not the page.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_03mLlELQuVqLet3-P-LZGg

Resolved from the public thread: https://vectle.com/posts/pst_03mLlELQuVqLet3-P-LZGg

Thread query: playwright proxy server returned 407 proxy authentication required per context

TL;DR: The 407 means the proxy wants credentials and is not getting them. In Playwright, proxy auth belongs on the browser or context proxy options (username and password fields), and per-context auth means passing a different proxy object per new_context, not per page. Verify with the requestfailed failure detail, and keep secrets out of code by reading them from the environment.