Discover / readability.openverbs.com

Consensus grade level

■ Challenge detected

Summarise a text's difficulty as a single consensus US grade level (averaging the five grade formulas), plus the Flesch Reading Ease, a plain-language difficulty band and an approximate age range.

x402
Base
USDC

Listed price: $0.002
Challenge detected: 9 of the last 9 checks
Median response: 183 ms
Last checked: 16 Oct, 13:59 UTC
In our index since: 26 Sept 2026

Endpoint

curl -i https://readability.openverbs.com/v1/grade
# 402 Payment Required: pay with an x402 client (USDC on Base),
# then send the same request again with the payment attached.

4 listed endpoints · on x402 Bazaar

Checks and payment terms on this page refer to the endpoint above. Other listed endpoints have not been checked individually.

Base URLhttps://readability.openverbs.com/v1

POST/grade$0.002Summarise a text's difficulty as a single consensus US grade level (averaging the five grade formulas), plus the Flesch Reading Ease, a plain-language difficulty band and an approximate age range.
POST/reading-time$0.002Estimate reading and speaking time for a text at configurable words-per-minute rates (defaults: 200 wpm reading, 130 wpm speaking).
POST/score$0.002Compute the standard English readability formulas — Flesch Reading Ease, Flesch–Kincaid grade, Gunning fog, SMOG, Coleman–Liau and ARI — along with the underlying sentence/word/syllable statistics. Empty text is a clean 400.
POST/syllables$0.002Count syllables per word and in total across the text.

A dash means the listing gives no price or method. Copy buttons copy the full URL.

Showing 4 of 4 listed endpoints.

Agents can find it through the Superstables MCP server and JSON API: GET /api/v1/services/readability.openverbs.com

Recent checks

4 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.16 Oct 2026

All 9 checks

When (UTC)	Result	HTTP	Response
16 Oct, 13:59 UTC	Challenge detected	402	181ms
15 Oct, 08:20 UTC	Challenge detected	402	196ms
14 Oct, 00:19 UTC	Challenge detected	402	194ms
12 Oct, 00:34 UTC	Challenge detected	402	215ms
10 Oct, 12:38 UTC	Challenge detected	402	184ms
9 Oct, 09:34 UTC	Challenge detected	402	177ms
8 Oct, 06:42 UTC	Challenge detected	402	183ms
7 Oct, 03:32 UTC	Challenge detected	402	182ms
4 Oct, 05:04 UTC	Challenge detected	402	169ms

Questions

Did our last probe detect a payment challenge?

At our last probe on 16 Oct, 13:59 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 Consensus grade level?

Its listed price is $0.002.

What payment terms does Consensus grade level 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 Consensus grade level listed?

In x402 Bazaar. Superstables first indexed it on 26 Sept 2026.

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