API Features
Browse the network by technical capability — authentication methods, protocols, delivery
mechanisms, deployment models, compliance certifications, and agent-native surfaces.
Providers describe features as free text in apis.yml — nearly 14,900 distinct
strings — so APIs.io maps them onto a canonical vocabulary. Each feature below lists every
provider that offers it, ranked by API Evangelist rating.
Webhooks
Outbound HTTP callbacks pushed on events.
REST API
Resource-oriented HTTP API over standard verbs.
Client SDKs
Official libraries in multiple languages.
OAuth 2.0
Delegated authorization via OAuth 2.0 flows.
Server-Sent Events & Streaming Responses
Incrementally streamed HTTP responses.
Open Source
Source code published under an open license.
Workflow Automation
Multi-step, event-triggered orchestration.
MCP Server
Model Context Protocol server for AI agents.
Observability & Monitoring
Metrics, traces, and logs for API usage.
Bearer Tokens & JWT
Signed bearer tokens and JWTs for stateless authentication.
Self-Hosting
Run the software in your own infrastructure.
Single Sign-On
Enterprise SSO via SAML or OIDC identity providers.
Rate Limiting
Documented request quotas and throttling behavior.
API Key Authentication
Simple key-based authentication for server-to-server calls.
Multi-Tenancy
Isolated tenants, workspaces, or organizations.
Containers & Kubernetes
Container images and Kubernetes-native deployment.
OpenAPI Specification
A machine-readable OpenAPI/Swagger contract.
Role-Based Access Control
Roles and permissions governing who can call what.
Sandbox Environment
A safe test environment with fake data.
Audit Logs
Immutable record of who did what, when.
Internationalization
Multi-language and multi-currency support.
Plugin & Extension Architecture
Extend the platform with custom plugins.
Filtering & Querying
Server-side filters, sorting, and field selection.
Multi-Region Deployment
Regional endpoints and cross-region replication.
Event Streaming
Durable event logs and stream consumption.
Batch & Bulk Operations
Submit or retrieve many records in one call.
High Availability
Redundant, fault-tolerant architecture.
No-Code / Low-Code Builder
Visual configuration without writing code.
API Versioning
Explicit versions with a stated compatibility policy.
File Upload & Object Storage
Binary upload, storage, and retrieval.
Auto Scaling
Capacity that grows and shrinks with load.
Prebuilt Connectors
A library of ready integrations to other systems.
WebSockets
Persistent bidirectional connections for live data.
API Gateway
Managed ingress with routing, auth, and policy.
Pagination
Cursor or offset paging through large result sets.
SOC 2
Independently audited SOC 2 controls.
API Discovery & Catalog
A machine-readable index of available APIs.
Agent Skills
Packaged skills and instructions for AI agents.
Full-Text Search
Indexed text search across the provider's corpus.
GraphQL API
Single-endpoint query language with client-shaped responses.
Edge Computing & CDN
Execution and caching at points of presence.
Developer Portal
A self-service hub for keys, docs, and apps.
Encryption at Rest & in Transit
TLS on the wire, encrypted storage, and key control.
Scheduled Jobs & Cron
Recurring, time-triggered execution.
Caching & Conditional Requests
ETags, cache headers, and conditional GETs.
SCIM User Provisioning
Automated user and group provisioning via SCIM.
API Governance
Linting, standards, and design rules enforced automatically.
Multiple Output Formats
JSON, XML, CSV, and other selectable representations.
Data Export
Full export of your data out of the platform.
Multi-Protocol Support
Several interfaces — REST, GraphQL, gRPC, streaming — on one product.
Private Networking
VPC peering, PrivateLink, and private endpoints.
White-Label & Branding
Rebrand the product as your own.
Infrastructure as Code
Terraform, Pulumi, or declarative configuration.
Multi-Factor Authentication
Second-factor and step-up authentication support.
Idempotency
Safe retries without duplicate side effects.
Uptime SLA
A contractual availability commitment.
CI/CD Integration
Hooks into build and deployment pipelines.
Historical Data & Time Series
Deep archives and time-series history, not just current state.
OpenAI-Compatible API
Drop-in compatibility with the OpenAI request shape.
Data Governance & Lineage
Cataloging, lineage, and quality controls over data.
Multi-Cloud Support
Runs on AWS, Azure, GCP, and beyond.
Request Signing
HMAC or cryptographically signed requests.
Secrets & Credential Management
Safe storage and rotation of keys and secrets.
API Documentation
Reference docs, guides, and examples.
API Testing Tooling
Built-in contract, integration, and load testing.
Embeddings & Vector Support
Vector embeddings and similarity search.
Real-Time Data
Live, low-latency data rather than delayed snapshots.
Fully Managed Service
Vendor operates the infrastructure for you.
Function Calling & Tool Use
Structured tool definitions LLMs can invoke.
Code & SDK Generation
Generate clients, types, or servers from the spec.
Embeddable UI Components
Drop-in widgets and hosted UI.
Fine-Grained Authorization
Attribute, resource, or field-level permission control.
gRPC
High-performance binary RPC over HTTP/2.
HIPAA Compliance
Protected health information handled under HIPAA.
Usage Analytics
Per-key and per-endpoint consumption reporting.
DDoS & Abuse Protection
Traffic filtering, WAF, and bot mitigation.
Human-in-the-Loop Controls
Approval gates on automated actions.
Status Page & Incident Communication
Public health status, incidents, and history.
Backup & Point-in-Time Recovery
Automated backups and restore to a prior state.
GDPR & Privacy Compliance
EU/UK privacy obligations and data-subject rights.
ISO 27001
Certified information-security management system.
LLM Inference
Hosted model inference endpoints.
Public / No Authentication
Open endpoints callable without credentials.
Basic Authentication
HTTP Basic username and password credentials.
MQTT & IoT Protocols
Lightweight pub/sub messaging for devices.
Postman Collection
A ready-to-run collection for API exploration.
Push Notifications
Mobile and browser push message delivery.
Fine-Tuning & Custom Models
Adapt hosted models to your own data.
JSON Responses
JSON as the primary request and response format.
PCI DSS
Cardholder-data handling certified to PCI DSS.
Feature Flags
Toggle behavior without redeploying.
CORS Support
Browser-callable endpoints with CORS headers.
FedRAMP & Government Authorization
Authorized for US public-sector workloads.
Vulnerability Disclosure & Bug Bounty
A published path for reporting security issues.
SOAP & XML Web Services
WSDL-described SOAP endpoints.
Structured Error Handling
Machine-readable, documented error responses.
Command-Line Interface
An official CLI for scripting and automation.
Deprecation Policy
Advance notice and sunset windows for changes.
RSS & Atom Feeds
Syndication feeds for content and updates.
Mutual TLS
Certificate-based client authentication at the transport layer.