API marketplaces for AI agents (2026)
RapidAPI, Apify, ApyHub, Zyla API Hub and upAPI, compared on what an agent builder asks first. upAPI is one of the five, so each row ends in a plain reading of where it is behind as well as where it is ahead.
Last checked 2026-10-07. Every competitor figure here was read from that vendor’s own pages on that date; where a vendor publishes none we say “not published” or “not found”. If this date has aged, check theirs before ours.
TL;DR: Which API marketplace should an AI agent use?
Pick RapidAPI or Zyla API Hub when you need breadth from independent providers and accept per-API pricing. Pick Apify when you need to run scrapers and keep the results. Pick ApyHub for a single-key catalog priced in atoms. Pick upAPI for a smaller catalog that one team runs, priced per call in published weights.
Five marketplaces side by side
| Feature | RapidAPI | Apify | ApyHub | Zyla API Hub | upAPI |
|---|---|---|---|---|---|
| MCP server support | Per API. When the provider enables MCP, a tool per endpoint is served from mcp.rapidapi.com and authenticated with your application key. | Hosted at mcp.apify.com over Streamable HTTP, with OAuth or a bearer token. Agents discover and run Actors from the Store; full-permission Actors and Rental Actors are excluded. | One connection at mcp.eu.apyhub.com, with browser sign-in or a bearer API key. Its MCP page counts 1,500+ certified tools. | Endpoint at mcp.zylalabs.com/mcp over streamable HTTP, with a bearer key or an apikey query parameter. Eight tools, including search_catalog and call_api. | Hosted at app.upapi.io/api/mcp with OAuth sign-in, or local with npx @upapi/mcp and an upapi_ key. Serves the catalog except the Social Media and Utility categories. Defaults to a compact set (search_ops and call_op, plus three direct tools); ?tools=full gives one tool per operation. Listed in the MCP Registry as io.github.DevinoSolutions/upapi-mcp. |
| Single API key across APIs | Yes. Its docs describe thousands of APIs reachable with a single account and API key. The key belongs to an application. | An Apify API token authorizes calls to the API and the hosted MCP server; each Actor run draws on the usage credits in your plan. | Yes. Its llms.txt says one API key and one subscription work across every service in the catalog. | Yes. Its homepage says a single account, a single API key and a single SDK. | Yes. One X-Api-Key and one pooled monthly quota across every public operation, with the same request and error shape on each. |
| Pricing model | Per API, set by each provider: a monthly subscription for the plan you select, plus overage fees above its quota. The hub pricing page sits behind a login, so we could not read a platform-wide price list; its docs price each API separately. | Free, Starter $19, Scale $199, Business $999 a month and Enterprise by quote, plus pay-as-you-go compute at $0.20 per compute unit on Free and Starter, falling to $0.13 on Business. Each Actor prices by event or by usage. | Atoms. Starter is free with 3,000 atoms a month, Pro is $16 for 100,000 and Pro+ is $42 for 500,000 (Medium Traffic plans; a Heavy Traffic tab also exists). Every plan includes every endpoint. | Per API; its /pricing page returns a 404, so we found no platform price list. For agents, billing is per successful call on a pay-as-you-go plan that activates on the first call. | Weighted units. Free at $0 for 1,000 a month, Starter $29 for 100,000, Pro $99 for 500,000 and Scale $499 for 5,000,000. Each operation publishes its own unit cost. |
| Free tier | Set per API. Many APIs have a free BASIC plan; a docs page it marks as legacy says freemium APIs require a credit card even for the free plan. | A Free plan with no credit card and $5 of prepaid usage a month. | Starter: 3,000 atoms a month and 5 requests a second. Its MCP page adds a free-tier cap of 5 API calls a day. | A "Free 7-Day Trial" badge on listings shown on its homepage. No account-wide free tier was stated. | Free plan: 1,000 weighted units a month across every public operation, with no trial clock. |
| Who runs the APIs | Independent providers. They add APIs, and a call passes through RapidAPI’s runtime to the provider. | Developers publish Actors, which are programs; customers run them on Apify’s platform and pay for the computing resources. | Mostly ApyHub. Its homepage says most of the catalog runs on its own infrastructure rather than being proxied, and a service hosted by its provider says so on its page. | Independent providers. call_api goes through the hub to the API’s own upstream provider, and providers list APIs through "Add Your API". | upAPI. Every public operation runs on upAPI’s own workers, and there is no third-party listing. Calls are synchronous with a 28-second cap. |
| Agent-facing docs | docs.rapidapi.com/llms.txt exists and indexes the doc pages. A quick-start page says that index also carries endpoints in OpenAPI, which the index file itself does not show. rapidapi.com/llms.txt returns 404. | docs.apify.com/llms.txt, plus the whole documentation as one Markdown file at llms-full.txt. We did not find an OpenAPI document for the Store. | apyhub.com/llms.txt and llms-full.txt, and every service page also as Markdown by appending .md. We did not find an OpenAPI document. | zylalabs.com/llms.txt and a top-500 catalog file at mcp.zylalabs.com/llms-catalog.txt; the full reference needs a key. We did not find an OpenAPI document. | upapi.io/llms.txt, upapi.io/docs/llms.txt and docs/llms-full.txt, a machine-readable catalog at app.upapi.io/api/catalog, and an OpenAPI document at app.upapi.io/api/openapi.json that carries each operation’s unit weight. |
How to read each row
- MCP server support. All five publish an MCP server, so that alone does not separate them. What differs is what the tools reach: RapidAPI’s depends on each provider enabling it, Apify’s excludes two Actor types, and upAPI’s withholds two categories. We have not measured how well any agent uses them.
- Single API key across APIs. All five use one account-level credential. One key is not one bill, though: RapidAPI and Zyla price each API separately, while ApyHub and upAPI draw every call from one allowance and Apify draws from plan credits.
- Pricing model. Five different meters: per-API subscriptions, compute and events, atoms, per successful call, and weighted units. Apify, ApyHub and upAPI publish one ladder for the whole account; for RapidAPI and Zyla we found none, so their cost depends on the APIs you pick.
- Free tier. Apify, ApyHub and upAPI state a free allowance for the whole account, in three different units, so the numbers are not comparable. RapidAPI’s and Zyla’s depend on the individual API.
- Who runs the APIs. This decides who you ask when a call fails. RapidAPI and Zyla broker independent providers, which is where their breadth comes from. Apify runs your choice of program. ApyHub and upAPI mostly operate the code themselves, at the cost of a narrower catalog.
- Agent-facing docs. All five publish some form of llms.txt. A machine-readable API description for the whole catalog is something we confirmed only for upAPI; for the others we say "not found", not "absent".
Trying upAPI costs nothing
The free plan needs no card, and every public operation is one POST with one header. Read the per-vendor comparisons below for the detail behind any one of these columns.
Questions about API marketplaces for agents
Which of these API marketplaces have an MCP server?
All five, on the pages we read on 2026-10-07. RapidAPI serves a tool per endpoint for APIs whose provider enables MCP, Apify hosts one at mcp.apify.com, ApyHub at mcp.eu.apyhub.com, Zyla API Hub at mcp.zylalabs.com, and upAPI at app.upapi.io/api/mcp. The authentication differs: OAuth, a bearer token, or a key in a query parameter.
Does one API key mean one bill?
Not by itself. RapidAPI prices each API through a plan its provider sets, and Zyla prices per API on its site, though its agent docs describe pay-as-you-go activated on first call. So a single key can still mean several plans. ApyHub and upAPI draw every call from one allowance (atoms and weighted units, respectively), and Apify draws from the usage credits in your plan. upAPI’s plans are $0, $29, $99 and $499 a month.
Which marketplaces run the APIs themselves and which proxy third parties?
RapidAPI and Zyla API Hub broker APIs run by independent providers, and a call goes through the hub to the provider. Apify runs Actors that developers publish. ApyHub says most of its catalog runs on its own infrastructure and marks the services that do not. Every public upAPI operation runs on upAPI’s own workers.
How many APIs does each marketplace list?
We do not rank by it, because the figures count different things and some contradict each other. RapidAPI’s docs say thousands of APIs. Zyla’s homepage says 10,000+ while its own category block counts roughly 8,700. ApyHub’s homepage says 400+ services and its llms.txt says 465. upAPI has 100+ public operations. APIs, services, Actors and operations are not the same unit.
Do these marketplaces publish an OpenAPI document and an llms.txt?
All five publish an llms.txt of some kind. upAPI also publishes an OpenAPI document for the whole catalog at app.upapi.io/api/openapi.json. RapidAPI says its docs index carries endpoints in OpenAPI and lets providers upload OpenAPI documents. We did not find a catalog-wide OpenAPI document for Apify, ApyHub or Zyla API Hub, which is not proof that none exists.
When is upAPI the wrong choice?
When you need an API that only an independent provider sells, since RapidAPI and Zyla list far more APIs than upAPI’s 100+ operations. When you need to run your own scraper and keep a dataset, which is Apify’s job. And when you want to publish and sell an API of your own: upAPI does not host third-party APIs.
Sources read on 2026-10-07: https://rapidapi.com/, https://docs.rapidapi.com/docs/faqs, https://docs.rapidapi.com/docs/what-is-rapidapi, https://docs.rapidapi.com/docs/consumer-quick-start-guide, https://docs.rapidapi.com/docs/consume-apis-using-ai, https://docs.rapidapi.com/llms.txt, https://apify.com/pricing, https://docs.apify.com/integrations/mcp, https://docs.apify.com/llms.txt, https://apyhub.com/pricing, https://apyhub.com/mcp, https://apyhub.com/llms.txt, https://zylalabs.com/, https://zylalabs.com/llms.txt, https://zylalabs.com/agents/setup.
API marketplaces for AI agents (2026). One-vendor comparisons: Apify, Bright Data, ScraperAPI, Serper, ApyHub, RapidAPI, ScrapingBee, Firecrawl, ScreenshotOne.