Clarity — can a reader hold the sentence on the first pass?
Persuasiveness — does the claim actually land, or just assert?
Structure — does the paragraph move, or circle?
Factuality — which sentences lean on things it can't back up?
Why
Most "is this good?" tools flatter you. WriteLens gives a working writer's read — clarity, persuasiveness, structure, and the sentences where the facts get shaky — with one concrete change to make first. Fast enough to run on every draft, honest enough to trust before you publish, or before you hand it back to a student.
For developers · the API underneath
One endpoint for the same signal, at scale
The same read, as JSON — for the tools, pipelines, and agents that need a quality signal without standing up an LLM stack.
curl -X POST https://writelens.ivixivi.workers.dev/v1/score \
-H "Content-Type: application/json" \
-d '{"text":"your text here"}'
Returns:
{
"clarity": 4,
"persuasiveness": 3,
"structure": 5,
"factuality_concerns": ["unsubstantiated claims about 'experts'"],
"overall": 4,
"suggestions": ["Replace 'various factors' with the actual factors"],
"char_count": 312
}
All scores are on a 0–10 scale.
Pricing
Free
$0
50 calls / day / IP
No API key needed
The web reader above
Paid
$49 / 1000 calls
API key + Bearer or X-API-Key auth
1000 included calls per 30-day period
For: writing tools, editors, pipelines, and agents
Subscribe
Pay $49 USDC on Base for a paid API key with 1000 included calls for 30 days. You'll get an address and a unique memo - send, then paste your transaction hash to unlock instantly.