--- title: The APIs That Charge Per Call And The APIs That Let You... description: Analysis of a catalog of 26,568 APIs finds two distinct cohorts building agent-readiness features: 71 providers offer a dry-run mode to simulate a call before... canonical: https://daily.dev/posts/the-apis-that-charge-per-call-and-the-apis-that-let-you-rehearse-are-two-different-sets-chqaapftb twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: The APIs That Charge Per Call And The APIs That Let You Rehearse Are Two Different Sets | daily.dev og:description: Analysis of a catalog of 26,568 APIs finds two distinct cohorts building agent-readiness features: 71 providers offer a dry-run mode to simulate a call before... og:url: https://daily.dev/posts/the-apis-that-charge-per-call-and-the-apis-that-let-you-rehearse-are-two-different-sets-chqaapftb og:image: https://api.daily.dev/og/posts/ChQaaPFTB.png og:image:alt: The APIs That Charge Per Call And The APIs That Let You Rehearse Are Two Different Sets og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # The APIs That Charge Per Call And The APIs That Let You Rehearse Are Two Different Sets **[API Evangelist](https://daily.dev/sources/apievangelist)** · 5 min read · 0 upvotes · 0 comments ## Summary Analysis of a catalog of 26,568 APIs finds two distinct cohorts building agent-readiness features: 71 providers offer a dry-run mode to simulate a call before committing, while 69 reference x402 for per-call payment (49 with the signal in an actual contract or manifest, not just prose). The intersection of these two groups is empty — no provider does both. The dry-run cohort skews infrastructure and developer tooling; the x402 cohort is almost entirely crypto-native. The conclusion drawn is that the market has not converged on a coherent 'agent-safe' category, and anyone building signed receipts for agent actions has to pitch dry-run providers and x402 providers separately, since neither group is close to combining simulation with settlement. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the x402 protocol used for in API payments? x402 is a protocol that lets APIs return an HTTP 402 Payment Required response for a specific request, priced in a stablecoin and settled without a signup, API key, or contract. Forty-nine providers in one catalog implement it inside actual contracts or commercial artifacts like OpenAPI specs, FinOps records, or MCP manifests, rather than just mentioning it in prose. The default spend cap on most agent x402 clients is around ten cents, signaling it targets high-frequency, low-value, machine-to-machine calls. _Developers evaluating machine-to-machine payment models can track how x402 adoption evolves on daily.dev._ ### Do any APIs support both dry-run simulation and per-call x402 payment? No, out of a catalog of 26,568 APIs, the set of providers offering a dry-run mode and the set doing per-call x402 payment do not overlap at all. The dry-run group (71 providers) is mostly infrastructure and developer tooling like Atlassian, Backstage, and Azure DevOps, while the x402 group (49 providers) is almost entirely crypto-native, including Arkham, thirdweb, and Fireblocks. Each solved a different problem for a different reason, so no provider combines both capabilities yet. _Anyone designing signed receipts for agent actions can follow how these two API cohorts converge, or don't, on daily.dev._ ## Similar posts on daily.dev - [Seventy-One APIs Will Let You Try A Call Without Committing It](https://daily.dev/posts/seventy-one-apis-will-let-you-try-a-call-without-committing-it-mue3uijkj) · API Evangelist · 2 upvotes · 1 comments - [foojay – a place for friends of OpenJDK](https://daily.dev/posts/foojay-a-place-for-friends-of-openjdk-khskkgtmg) · Foojay.io · 1 upvotes · 0 comments - [AI agents can browse the web. Now they need a way to pay for it.](https://daily.dev/posts/ai-agents-can-browse-the-web-now-they-need-a-way-to-pay-for-it--xu9muwtef) · The Next Web · 1 upvotes · 0 comments - [A Guide to 5 Agent Payment Protocols](https://daily.dev/posts/a-guide-to-5-agent-payment-protocols-fidninthl) · Nordic APIs · 1 upvotes · 0 comments --- Tags: [#architecture](https://daily.dev/tags/architecture), [#agentic-ai](https://daily.dev/tags/agentic-ai) [View this post on daily.dev](https://daily.dev/posts/the-apis-that-charge-per-call-and-the-apis-that-let-you-rehearse-are-two-different-sets-chqaapftb) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"The APIs That Charge Per Call And The APIs That Let You Rehearse Are Two Different Sets","url":"https://daily.dev/posts/the-apis-that-charge-per-call-and-the-apis-that-let-you-rehearse-are-two-different-sets-chqaapftb","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/the-apis-that-charge-per-call-and-the-apis-that-let-you-rehearse-are-two-different-sets-chqaapftb"},"datePublished":"2026-08-21T00:09:27.879Z","dateModified":"2026-09-14T07:31:14.306Z","description":"Analysis of a catalog of 26,568 APIs finds two distinct cohorts building agent-readiness features: 71 providers offer a dry-run mode to simulate a call before...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/cc40996d4b4ff2db9e8ee05cc1dfe782?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/cc40996d4b4ff2db9e8ee05cc1dfe782?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"API Evangelist","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"API Evangelist","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/a36244ae67bc4f41a605f780267ecb5f","url":"https://daily.dev/sources/apievangelist"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/the-apis-that-charge-per-call-and-the-apis-that-let-you-rehearse-are-two-different-sets-chqaapftb","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"architecture,agentic-ai","timeRequired":"PT5M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"API Evangelist","item":"https://daily.dev/sources/apievangelist"},{"@type":"ListItem","position":3,"name":"The APIs That Charge Per Call And The APIs That Let You Rehearse Are Two Different Sets"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/the-apis-that-charge-per-call-and-the-apis-that-let-you-rehearse-are-two-different-sets-chqaapftb#faq","mainEntity":[{"@type":"Question","name":"What is the x402 protocol used for in API payments?","acceptedAnswer":{"@type":"Answer","text":"x402 is a protocol that lets APIs return an HTTP 402 Payment Required response for a specific request, priced in a stablecoin and settled without a signup, API key, or contract. 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