API Building Blocks
Discover the APIs behind chat, UI, voice, video, data, automation, and agents. Compare capabilities and choose the right building blocks for headless and agentic software.
11 listings · Last updated Sep 14, 2026
Showing 11 of 11 listings
| Compare | Name | Category | Pricing model | Authentication | Free tier | Open source |
|---|---|---|---|---|---|---|
Context.devFeatured A web data API for scraping and crawling sites, extracting structured content, retrieving brand and company data, and enriching entities for AI agents and products. | Data & Knowledge | Freemium | Bearer token | ✓Yes | —No | |
A hosted search and discovery API for indexing records, running keyword and AI-assisted search, configuring ranking, filtering results, and adding recommendations and personalization. | UI & Experiences | Freemium | API key | ✓Yes | —No | |
An identity and user management API for users, sessions, organizations, invitations, tokens, machine authentication, API keys, and application authentication workflows. | Identity & Security | Freemium | Bearer token | ✓Yes | —No | |
A voice and audio API for text to speech, speech to text, conversational voice agents, dubbing, sound effects, voice transformation, and audio processing. | Voice & Audio | Freemium | API key | ✓Yes | —No | |
A video generation API for creating avatar videos, translating and dubbing video, generating speech, producing videos from templates, and working with avatar, voice, and template libraries. | Video & Avatars | Usage-based | API key | —No | —No | |
A durable execution and workflow API for event-driven functions, background jobs, queues, retries, concurrency, throttling, scheduling, and workflow observability. | Automation & Orchestration | Freemium | API key | ✓Yes | ✓Yes | |
A model API for building text, reasoning, multimodal, realtime, image, audio, and agentic applications through hosted models and tools. | Models & Agents | Usage-based | API key | —No | —No | |
A managed vector database and inference API for storing and searching records, generating embeddings, reranking results, and building retrieval and knowledge applications. | Data & Knowledge | Freemium | API key | ✓Yes | —No | |
An email API for sending and receiving transactional email, managing domains, contacts, broadcasts, templates, webhooks, and delivery events. | Chat & Messaging | Freemium | API key | ✓Yes | —No | |
A payments and financial infrastructure API for accepting payments, managing subscriptions, sending payouts, running platforms and marketplaces, and automating revenue workflows. | Payments & Commerce | Usage-based | API key | —No | —No | |
A platform API for managing deployments, projects, domains, environment variables, logs, caches, integrations, teams, and other application infrastructure. | Infrastructure & Observability | Freemium | Bearer token | ✓Yes | —No |