CryptAPI primary sources — 2026-04-30

Project status in this pass

• No canonical standalone whitepaper or litepaper surfaced.
• The clearest current source of truth is the official docs corpus, llms.txt, raw docs export, and the main site.
• One useful nuance in this pass: the custom API flow is documented as accountless and wallet-address-first, while the ecommerce/plugin materials mention API-key-style setup. That likely reflects two product surfaces rather than a single contradictory model.

Primary-source snapshots

1) Main site

• URL: https://cryptapi.io/
• Key excerpt:
  • The homepage says CryptAPI is a “leading crypto payment gateway” trusted by “thousands of services worldwide.”
  • It claims fees “as low as 0.25%,” automatic settlement into the merchant wallet, publicly available plugin source code, and that registrations or API keys are not mandatory.
  • This is the clearest high-level statement that CryptAPI is positioning itself around simple merchant acceptance and direct wallet settlement.

2) Docs llms.txt

• URL: https://docs.cryptapi.io/llms.txt
• Key excerpt:
  • States that CryptAPI endpoints do not use a v1 path prefix.
  • Calls out six “critical guides,” with the custom-payment-flow guide treated as the central implementation reference.
  • Repeatedly warns that transactions below minimums are ignored and funds are lost, and also documents webhook IPs, official libraries, and raw markdown access via the docs API.
  • This was the fastest way to recover the real integration model and safety-critical implementation details.

3) Custom payment flow guide

• URL: https://docs.cryptapi.io/get-started/custom-payment-flow
• Raw export: https://docs.cryptapi.io/api/raw/get-started/custom-payment-flow
• Key excerpt:
  • Says merchants can build a fully customized payment experience with address creation, UI control, and webhook handling.
  • Explicitly says users do not need to create an account and only need to provide a wallet address where funds should be received.
  • Documents ticker-based create endpoints, pending and confirmed webhooks, logs-based status checking, and testing recommendations using Litecoin.
  • Strongly warns that minimum transaction amounts must always be shown and validated because sub-minimum transactions are ignored.

4) Service information endpoint docs

• URL: https://docs.cryptapi.io/api/info
• Key excerpt:
  • Documents the service-information endpoint as the source for supported blockchains, cryptocurrencies, and tokens.
  • Exposes minimum_transaction_coin, minimum_fee_coin, fee percentage, fee tiers, optional fiat prices, and update timing.
  • This is the clearest proof that CryptAPI is publishing operational metadata needed for real merchant integrations, not just checkout marketing.

5) Webhook signature verification guide

• URL: https://docs.cryptapi.io/webhooks/verify-webhook-signature
• Raw export: https://docs.cryptapi.io/api/raw/webhooks/verify-webhook-signature
• Key excerpt:
  • Says every webhook is signed with a 1024-bit RSA SHA256 signature sent in the x-ca-signature header.
  • Documents what is signed for GET versus POST delivery and points integrators to the public key at https://api.cryptapi.io/pubkey/.
  • Includes implementation examples in multiple languages and recommends HTTPS, rate limiting, idempotency, and logging of verification failures.

6) Ecommerce integration page

• URL: https://docs.cryptapi.io/get-started/ecommerce
• Key excerpt:
  • Says CryptAPI offers official plugins for major ecommerce platforms plus custom integration support and low-code options.
  • Mentions plugin installation, payment configuration, test mode, and “enter your API key” setup steps.
  • This matters because it suggests CryptAPI has expanded beyond the pure wallet-address flow into a more managed plugin/integration surface.

7) GitHub organization

• URL: https://github.com/cryptapi
• Notes:
  • The GitHub organization is first-party evidence that official libraries and ecommerce plugins are a maintained part of the product surface.
  • In discovery terms, the GitHub org helps confirm CryptAPI is not just a landing page with undocumented endpoints.

Working conclusion

CryptAPI is best cataloged as wallet-forwarding merchant payments infrastructure with a docs-first implementation surface. The key distinction is that it packages address generation, price conversion, minimum-amount safety, QR generation, plugin/SDK distribution, and signed payment webhooks into one integration model without forcing every merchant into a heavyweight custodial or account-centric setup.