# APIs.io — Federated API Discovery Network (Full Reference)

> APIs.io indexes API providers from across the public internet — their APIs, schemas, event-driven specs, governance rules, vocabularies, and JSON-LD contexts. Every page on the network is published as both an HTML document for humans and a structured artifact for agents.

This llms-full.txt is the dense reference variant of [/llms.txt](https://apis.io/llms.txt). It contains the network's structural map and pointers to the per-subdomain feeds an agent needs to ground against. Search indexing, AI grounding/RAG, and AI training are explicitly permitted — see https://apis.io/terms/.

Current network counts:

- **6445 providers**
- **22615 APIs**
- **98952 JSON Schemas**
- **446 AsyncAPI specifications**
- **4153 JSON-LD contexts**
- **1718 Spectral governance rulesets**
- **4725 pricing plan profiles**
- **4736 rate-limit profiles**
- **4689 FinOps profiles**

## How to consume this network as an agent

1. **Discover URLs**: fetch the RFC 9727 linkset at [/.well-known/api-catalog](https://apis.io/.well-known/api-catalog). Each `anchor` is a provider or API page; each `service-doc` / `service-desc` / `describedby` link is the typed document for that resource.
2. **Search**: hit [search-index.json](https://apis.io/search-index.json) for full-text matches, or [/.well-known/api-catalog](https://apis.io/.well-known/api-catalog) for structured discovery.
3. **Ground**: every per-entity page (`providers.apis.io/providers/<slug>/`, `apis.apis.io/apis/<provider>/<api>/`, etc.) embeds an `overview` paragraph in its `<meta name="description">` and renders the same prose visibly above the cards. The prose is generated deterministically from the structured frontmatter, so two pages cannot collapse to identical text.

## Industry verticals (29 industries)

The network maps every provider to one or more industries — financial services, healthcare, manufacturing, transportation, etc. Industries describe **who buys an API** (financial services, healthcare). Browse them at [industries.apis.io](https://industries.apis.io/).


### AI & Machine Learning (575 providers, 2973 APIs)

`ai-machine-learning` · [https://industries.apis.io/industries/ai-machine-learning/](https://industries.apis.io/industries/ai-machine-learning/)

Foundation models, ML platforms, generative AI, and AI agents.

### Cloud & Developer Tools (571 providers, 3828 APIs)

`cloud-developer-tools` · [https://industries.apis.io/industries/cloud-developer-tools/](https://industries.apis.io/industries/cloud-developer-tools/)

Cloud platforms, developer infrastructure, and the API-management stack.

### Media & Entertainment (340 providers, 1355 APIs)

`media-entertainment` · [https://industries.apis.io/industries/media-entertainment/](https://industries.apis.io/industries/media-entertainment/)

Streaming, publishing, gaming, music, video, and entertainment distribution.

### Security & Identity (338 providers, 2129 APIs)

`security-identity` · [https://industries.apis.io/industries/security-identity/](https://industries.apis.io/industries/security-identity/)

Cybersecurity, identity-and-access, fraud prevention, and trust infrastructure.

### Government & Public Sector (299 providers, 766 APIs)

`government` · [https://industries.apis.io/industries/government/](https://industries.apis.io/industries/government/)

Federal, state, and local government data, services, and civic-tech platforms.

### Financial Services (268 providers, 1346 APIs)

`financial-services` · [https://industries.apis.io/industries/financial-services/](https://industries.apis.io/industries/financial-services/)

Banking, lending, wealth management, capital markets, and core financial infrastructure.

### Transportation & Logistics (242 providers, 845 APIs)

`transportation-logistics` · [https://industries.apis.io/industries/transportation-logistics/](https://industries.apis.io/industries/transportation-logistics/)

Freight, shipping, last-mile delivery, automotive, and mobility platforms.

### Retail & E-Commerce (240 providers, 1512 APIs)

`retail-ecommerce` · [https://industries.apis.io/industries/retail-ecommerce/](https://industries.apis.io/industries/retail-ecommerce/)

Storefronts, marketplaces, point-of-sale, inventory, and consumer commerce.

### Marketing & Advertising (211 providers, 1292 APIs)

`marketing-advertising` · [https://industries.apis.io/industries/marketing-advertising/](https://industries.apis.io/industries/marketing-advertising/)

Ad platforms, marketing automation, sales tools, CRM, and customer engagement.

### Payments (187 providers, 1432 APIs)

`payments` · [https://industries.apis.io/industries/payments/](https://industries.apis.io/industries/payments/)

Card processing, ACH, wallets, subscriptions, invoicing, and payment orchestration.

### Healthcare & Life Sciences (171 providers, 553 APIs)

`healthcare` · [https://industries.apis.io/industries/healthcare/](https://industries.apis.io/industries/healthcare/)

Clinical systems, payors, pharma, medical devices, and digital health.

### IoT & Robotics (150 providers, 719 APIs)

`iot-robotics` · [https://industries.apis.io/industries/iot-robotics/](https://industries.apis.io/industries/iot-robotics/)

Connected devices, industrial sensors, robotics, and hardware platforms.

### Open Data (141 providers, 483 APIs)

`open-data` · [https://industries.apis.io/industries/open-data/](https://industries.apis.io/industries/open-data/)

Government and civic open data, public datasets, and reference data.

### Telecommunications (131 providers, 899 APIs)

`telecommunications` · [https://industries.apis.io/industries/telecommunications/](https://industries.apis.io/industries/telecommunications/)

Carriers, mobile networks, messaging, voice, and communications-platform-as-a-service.

### Fintech (126 providers, 796 APIs)

`fintech` · [https://industries.apis.io/industries/fintech/](https://industries.apis.io/industries/fintech/)

Consumer and SMB-facing financial products built API-first.

### Blockchain & Web3 (124 providers, 654 APIs)

`blockchain-web3` · [https://industries.apis.io/industries/blockchain-web3/](https://industries.apis.io/industries/blockchain-web3/)

Crypto exchanges, DeFi protocols, NFTs, and blockchain infrastructure.

### Supply Chain & Procurement (112 providers, 645 APIs)

`supply-chain-procurement` · [https://industries.apis.io/industries/supply-chain-procurement/](https://industries.apis.io/industries/supply-chain-procurement/)

Procurement platforms, supplier networks, and supply-chain visibility.

### Energy & Utilities (97 providers, 263 APIs)

`energy-utilities` · [https://industries.apis.io/industries/energy-utilities/](https://industries.apis.io/industries/energy-utilities/)

Oil and gas, electric utilities, renewables, mining, and the broader energy stack.

### Manufacturing & Industrial (93 providers, 430 APIs)

`manufacturing-industrial` · [https://industries.apis.io/industries/manufacturing-industrial/](https://industries.apis.io/industries/manufacturing-industrial/)

Discrete and process manufacturing, industrial IoT, and supply-side production.

### Human Resources (87 providers, 586 APIs)

`human-resources` · [https://industries.apis.io/industries/human-resources/](https://industries.apis.io/industries/human-resources/)

Recruiting, ATS, payroll, workforce management, and HR systems.

### Aerospace & Defense (80 providers, 246 APIs)

`aerospace-defense` · [https://industries.apis.io/industries/aerospace-defense/](https://industries.apis.io/industries/aerospace-defense/)

Aviation OEMs, defense systems, satellites, and aerospace infrastructure.

### Construction & Real Estate (76 providers, 303 APIs)

`construction-real-estate` · [https://industries.apis.io/industries/construction-real-estate/](https://industries.apis.io/industries/construction-real-estate/)

Property data, construction tech, real-estate marketplaces, and PropTech.

### Agriculture & Food (67 providers, 182 APIs)

`agriculture-food` · [https://industries.apis.io/industries/agriculture-food/](https://industries.apis.io/industries/agriculture-food/)

Farm management, food production, supply, and the AgTech stack.

### Travel & Hospitality (61 providers, 343 APIs)

`travel-hospitality` · [https://industries.apis.io/industries/travel-hospitality/](https://industries.apis.io/industries/travel-hospitality/)

Airlines, hotels, booking platforms, OTAs, and tourism infrastructure.

### Insurance (59 providers, 221 APIs)

`insurance` · [https://industries.apis.io/industries/insurance/](https://industries.apis.io/industries/insurance/)

Underwriting, claims, policy administration, and insurance distribution.

### Climate & Sustainability (58 providers, 246 APIs)

`climate-sustainability` · [https://industries.apis.io/industries/climate-sustainability/](https://industries.apis.io/industries/climate-sustainability/)

Carbon accounting, ESG reporting, climate data, and sustainability platforms.

### Sports & Fitness (51 providers, 207 APIs)

`sports-fitness` · [https://industries.apis.io/industries/sports-fitness/](https://industries.apis.io/industries/sports-fitness/)

Pro-league stats, fitness platforms, wearables, and athlete data.

### Education (38 providers, 166 APIs)

`education` · [https://industries.apis.io/industries/education/](https://industries.apis.io/industries/education/)

Learning platforms, school information systems, and ed-tech delivery.

### Legal (37 providers, 247 APIs)

`legal` · [https://industries.apis.io/industries/legal/](https://industries.apis.io/industries/legal/)

Practice-management, e-discovery, contracts, regulatory, and LegalTech.


## Sister subdomains in the APIs.io network

Each sister site is a separate Git repo published as its own GitHub Pages deploy. Every site exposes a sitemap, a search index, and an `llms.txt`.

| Subdomain | What it indexes | llms.txt |
|---|---|---|
| [apis.io](https://apis.io/) | Hub: search, blog, taxonomy, build pipeline | [/llms.txt](https://apis.io/llms.txt) |
| [developer.apis.io](https://developer.apis.io/) | Developer portal & feeds | [/llms.txt](https://developer.apis.io/llms.txt) |
| [providers.apis.io](https://providers.apis.io/) | API provider profiles (6445) | [/llms.txt](https://providers.apis.io/llms.txt) |
| [apis.apis.io](https://apis.apis.io/) | Individual API records (22615) | [/llms.txt](https://apis.apis.io/llms.txt) |
| [industries.apis.io](https://industries.apis.io/) | Industry-vertical index (29) | [/llms.txt](https://industries.apis.io/llms.txt) |
| [regions.apis.io](https://regions.apis.io/) | Sales-region index (17) | [/llms.txt](https://regions.apis.io/llms.txt) |
| [skills.apis.io](https://skills.apis.io/) | Agent Skill index (82 providers) | [/llms.txt](https://skills.apis.io/llms.txt) |
| [mcp.apis.io](https://mcp.apis.io/) | MCP server index (225 providers) | [/llms.txt](https://mcp.apis.io/llms.txt) |
| [schemas.apis.io](https://schemas.apis.io/) | JSON Schemas (98952) | [/llms.txt](https://schemas.apis.io/llms.txt) |
| [asyncapi.apis.io](https://asyncapi.apis.io/) | Event-driven specs (446) | [/llms.txt](https://asyncapi.apis.io/llms.txt) |
| [json-ld.apis.io](https://json-ld.apis.io/) | JSON-LD contexts (4153) | [/llms.txt](https://json-ld.apis.io/llms.txt) |
| [rules.apis.io](https://rules.apis.io/) | Spectral rulesets (1718) | [/llms.txt](https://rules.apis.io/llms.txt) |
| [vocabularies.apis.io](https://vocabularies.apis.io/) | Provider tag vocabularies | [/llms.txt](https://vocabularies.apis.io/llms.txt) |
| [tags.apis.io](https://tags.apis.io/) | Tag index | [/llms.txt](https://tags.apis.io/llms.txt) |
| [examples.apis.io](https://examples.apis.io/) | API usage examples | [/llms.txt](https://examples.apis.io/llms.txt) |
| [plans.apis.io](https://plans.apis.io/) | Pricing plans (4725) | [/llms.txt](https://plans.apis.io/llms.txt) |
| [rate-limits.apis.io](https://rate-limits.apis.io/) | Rate-limit profiles (4736) | [/llms.txt](https://rate-limits.apis.io/llms.txt) |
| [finops.apis.io](https://finops.apis.io/) | FinOps profiles (4689) | [/llms.txt](https://finops.apis.io/llms.txt) |

## Machine-readable feeds

- **RFC 9727 linkset (full network)**: https://apis.io/.well-known/api-catalog
- **RFC 9727 linkset (providers slice)**: https://providers.apis.io/.well-known/api-catalog
- **RFC 9727 linkset (APIs slice)**: https://apis.apis.io/.well-known/api-catalog
- **APIs.json self-description**: https://apis.io/apis.json
- **Sitemap index (all subdomains)**: https://apis.io/sitemap_index.xml
- **Cross-network stats**: https://apis.io/insights/index.json
- **Top providers**: https://apis.io/insights/top-providers.json
- **Top tags**: https://apis.io/insights/top-tags.json

## Page structure (what an agent gets per entity)

Every entity page in the network includes:

1. A short factual description (from the upstream APIs.json).
2. A 1–3 paragraph generated prose `overview` (unique per entity, derived from the structured data).
3. The structured artifact list — APIs, schemas, resources, etc. — with deep links to each.
4. JSON-LD structured data:
   - `Organization` + `BreadcrumbList` on provider pages
   - `WebAPI` + `BreadcrumbList` on individual API pages
   - `Dataset` (DataCatalog: APIs.io) + `BreadcrumbList` on schema, plan, ratelimit, finops pages
5. Open Graph and Twitter Card metadata derived from the overview.
6. Cross-links to sibling entities ("Other APIs from this provider").

## Related projects

- [APIs.json](https://apisjson.org): The machine-readable API discovery format every profile in this network uses
- [API Commons](https://apicommons.org): Standard vocabulary of common operational properties referenced from APIs.json
- [Naftiko](https://github.com/naftiko/framework): Open-source framework that runs capability specs as REST, MCP, and Agent Skill surfaces
- [api-evangelist](https://github.com/api-evangelist): Upstream Git-versioned provider profile repos this network is built from

## License and usage

All content on APIs.io is published as a public catalog of API metadata, intended for both human and machine consumption. Search indexing, AI grounding/RAG, and AI training are explicitly permitted. See https://apis.io/terms/ for the full terms.