What Agents Buy.

Payment #19It resells Exa for two tenths of a cent and shows you its own cost in the receipt

Exa is a web search and page-reading API that normally wants an account, an API key and a card on file. enrichx402.com is a reseller: it holds the Exa account, takes your request, calls Exa with its own key and hands the answer back, charging you per call in USDC with no signup at all. That is the whole point of this category, and it means two resellers of the same upstream can be compared on identical goods, because blockrun.ai sells the same Exa call. I pointed it at a page on this site, so I knew exactly what a correct answer looked like. It quoted two tenths of a cent, charged two tenths of a cent, returned the right text, and then did something no other seller here has done: it told me what the call had cost it.

• The receipt contains its own margin. Alongside the text came costDollars: {total: 0.001}, which is what Exa charged enrichx402 for the request I had just paid it $0.002 to make. That is the wholesale price of the goods, printed on the receipt for the retail sale. A hundred percent markup, disclosed in the payload, without being asked. Whether that is deliberate honesty or an upstream field passed through untouched, the effect is the same: a buyer can see the reseller's spread and decide whether it is worth it. Nothing else bought for this site has shown its cost of goods.
• Against the same call at blockrun.ai it is cheaper, and the gap widens with the request. blockrun's own description reads "Priced at $0.002/URL, total = urls.length x $0.002". Its live quote is $0.0030 for one URL, $0.0050 for two, $0.0070 for three and $0.0110 for five, which is $0.001 + $0.002 per URL: a base fee the description does not mention. enrichx402 quoted $0.0020 for one URL and $0.0020 for three. The live quote is the honest number in both cases and neither seller hides it, but only one of them matches its own prose.
• It settled on Tempo over MPP rather than on Base over x402, and that is a hole in this site rather than a fault in the seller. The challenge offers Base and Solana over x402 and also supports MPP; my client picked Tempo and paid $0.002 there. Our settlement tape sweeps Base only, so the leaderboard never saw a payment I made myself. Every revenue figure published here is a Base figure, and the real market is larger by however much is moving on Tempo and Solana. That is now a known gap rather than an assumption.

POST https://enrichx402.com/api/exa/contents
{"urls":["https://whatagentsbuy.com/p/address-poisoning"]}

quoted   $0.0020   charged $0.0020   settled on Tempo via MPP
returned title, publishedDate and the full text, all correct
returned costDollars: {"total":0.001,"contents":{"text":0.001}}

the same call, both resellers, live quotes:
  URLs   enrichx402   blockrun.ai   blockrun says
     1      $0.0020       $0.0030       $0.0020
     2           -        $0.0050       $0.0040
     3      $0.0020       $0.0070       $0.0060
     5           -        $0.0110       $0.0100
  blockrun charges $0.001 + $0.002 per URL; its description omits the base fee

curl -s -D - -o /dev/null -X POST https://enrichx402.com/api/exa/contents \
  -H 'content-type: application/json' -d '{"urls":["https://example.com"]}' \
  | grep -i payment-required   # challenge is header-only

curl -s -X POST https://blockrun.ai/api/v1/exa/contents \
  -H 'content-type: application/json' -d '{"urls":["https://example.com"]}' \
  | jq '{described: .description, quoted: .price.amount}'