Discover / kevinhoff.com

x-preflight

■ Challenge detected

X Preflight: read a draft post against X's open-sourced ranking code. Returns what is already settled before you post, whether it enters the pool strangers are drawn from, how long it stays retrievable, which filters delete it, and which gates nobody can know in advance. Every claim cites a file and line in X's published source. Never writes the post. Nothing stored.

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

Endpoint

curl -i https://kevinhoff.com/api/paid/grade
# 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/kevinhoff.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 detected402679ms

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 x-preflight?

Its listed price is $0.01.

What payment terms does x-preflight advertise?

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

Where is x-preflight listed?

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

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