Duo Data Utilities
https://api.duoleads.com/a2a
● down
a2a-agent
33 independent pay-per-call data utilities (identifiers, time, text, encodings, geodesy, blockchain primitives, reference tables, number arithmetic). $0.05 per call, payable over x402 (USDC on Base, eip155:8453). No account, no API key. A2A: JSON-RPC at https://api.duoleads.com/a2a; send a DataPart {"skill": "<skill id>", "params": {...}}; skill execution is paid through the a2a-x402 extension. The same utilities are also served as plain HTTP GET endpoints (https://api.duoleads.com/openapi.json) and as MCP tools over Streamable HTTP at https://api.duoleads.com/mcp (tools/list free, tools/call paid).
Category
a2a-agent
Chains
base
Price
$0.0500 USDC / call
Quality grade
How grading works
D
31.4 / 100
capped at D while down
Availability
0.0 / 40
Endpoint did not respond
Payability
20.0 / 20
- ✓ Answers a real HTTP 402 challenge
- ✓ Publishes a /.well-known/x402 descriptor
- ✓ Payment address on record
- ✓ Settlement network declared
- ✓ Price declared
Demand
11.4 / 40
2 distinct payers, 138 USDC transfers in the last 30 days
Owner verified
0.0 / 3
Nobody has claimed this listing yet
Endpoint last checked 9 h ago.
On-chain activity last read 11 d ago.
Availability and on-chain demand are both re-probed daily; the grade
updates automatically on the next pass.
Paid endpoints
33 resource(s) advertised by this origin.
https://api.duoleads.com/v1/id/national
https://api.duoleads.com/v1/id/gs1
https://api.duoleads.com/v1/id/security
https://api.duoleads.com/v1/id/iban
https://api.duoleads.com/v1/id/iban-build
https://api.duoleads.com/v1/time/zone
https://api.duoleads.com/v1/time/dst
https://api.duoleads.com/v1/time/business-days
https://api.duoleads.com/v1/time/rrule
https://api.duoleads.com/v1/time/calendar
https://api.duoleads.com/v1/text/slug
https://api.duoleads.com/v1/text/transliterate
https://api.duoleads.com/v1/text/unicode
https://api.duoleads.com/v1/text/similarity
https://api.duoleads.com/v1/code/url
https://api.duoleads.com/v1/code/idn
https://api.duoleads.com/v1/code/semver
https://api.duoleads.com/v1/code/hash
https://api.duoleads.com/v1/code/jwt
https://api.duoleads.com/v1/geo/geohash
https://api.duoleads.com/v1/geo/pluscode
https://api.duoleads.com/v1/geo/polygon
https://api.duoleads.com/v1/geo/distance
https://api.duoleads.com/v1/chain/address
https://api.duoleads.com/v1/chain/selector
https://api.duoleads.com/v1/ref/nuts
https://api.duoleads.com/v1/ref/airport
https://api.duoleads.com/v1/ref/currency
https://api.duoleads.com/v1/ref/country
https://api.duoleads.com/v1/num/radix
https://api.duoleads.com/v1/num/words
https://api.duoleads.com/v1/num/stats
https://api.duoleads.com/v1/num/allocate
How to call
cURL · x402-fetch / x402-axios will auto-handle 402
curl -sS -i -X GET https://api.duoleads.com/a2a # expect HTTP 402 Payment Required (about 0.05 USDC/call)/.well-known/x402.json
https://api.duoleads.com/.well-known/x402
Listed in
Directories this entry was found in.
a2a