Discover / cors-header-checker.underscoredone.com

CORS Header Checker

■ Challenge detected

Sends a real request to any URL you provide, attaches an Origin header, and reads back all six standard cross-origin permission headers the server returns. Tells you whether cross-origin requests are enabled at all, whether your specific origin is permitted, and shows every permission value exactly as the server sent it. Useful for finding why a browser is blocking a request, confirming a new deployment is configured correctly, or auditing whether a public API allows credentialed calls.

Listed price
$0.01
Challenge detected
1 of the last check
Median response
757 ms
Last checked
14 Oct, 18:06 UTC
In our index since
14 Oct 2026

Endpoint

curl -i https://cors-header-checker.underscoredone.com/check
# 402 Payment Required: pay with an x402 client (USDC on Base),
# then send the same request again with the payment attached.

Agents can find it through the Superstables MCP server and JSON API: GET /api/v1/services/cors-header-checker.underscoredone.com

Recent checks

14 Oct 2026One bar per check, showing up to 20 recent checks. Coloured bars show relative response time, with a minimum visible height; full-height grey bars mean no challenge was detected. “Challenge detected” means HTTP 402 or another detected payment-challenge signal.14 Oct 2026
All 1 checks
When (UTC)ResultHTTPResponse
14 Oct, 18:06 UTCChallenge detected402757ms

Questions

Did our last probe detect a payment challenge?

At our last probe on 14 Oct, 18:06 UTC, it returned HTTP 402 or another detected payment-challenge signal. This check did not test payment, delivery or compatibility with the Superstables client.

What price is recorded for CORS Header Checker?

Its listed price is $0.01.

What payment terms does CORS Header Checker advertise?

The listing advertises x402, Base, Solana and USDC. It names cdp as its facilitator. Check the seller's current payment challenge and authentication requirements before paying.

Where is CORS Header Checker listed?

In x402 Bazaar. Superstables first indexed it on 14 Oct 2026.

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