21st

21st

21st.dev
+
+

Related Products

  • Gemini Enterprise Agent Platform
    999 Ratings
    Visit Website
  • BAND
    3 Ratings
    Visit Website
  • Retool
    593 Ratings
    Visit Website
  • Apify
    1,441 Ratings
    Visit Website
  • cside
    37 Ratings
    Visit Website
  • Google Cloud Run
    349 Ratings
    Visit Website
  • JetBrains Junie
    12 Ratings
    Visit Website
  • Checksum.ai
    1 Rating
    Visit Website
  • LM-Kit.NET
    29 Ratings
    Visit Website
  • Reflectiz
    33 Ratings
    Visit Website

About

21st is a developer platform that provides the fastest way to add AI agents directly into applications. The platform offers an SDK that allows developers to define, deploy, and run AI agents with minimal infrastructure setup. Developers can integrate agents using popular frameworks such as Next.js, React, TypeScript, Python, and Node.js. 21st includes built-in features like chat interfaces, session history, tool execution, memory, and real-time streaming responses. The platform also manages backend components such as sandboxed execution environments, authentication, rate limits, and observability. With support for Claude Code and Codex runtimes, developers can build agents that interact with tools, files, and APIs securely. By handling infrastructure and deployment automatically, 21st enables teams to launch production-ready AI agents quickly.

About

Preloop is the open source AI agent control plane for agents that take real actions. It combines an MCP firewall for tool access, an AI model gateway for cost, safety, and attribution, policy-as-code with human approvals, runtime session observability, and audit trails in a single self-hostable platform. AI agents can deploy code, change infrastructure, move money, touch production data, and burn model spend in seconds, so Preloop helps teams control what agents can do, how much they spend, and which actions require human approval. It works with OpenClaw, Hermes, Claude Code, Codex CLI, Cursor, Gemini CLI, Windsurf, Cline, OpenCode, and any MCP-compatible agent or managed runtime. Access rules can inspect arguments and context, not just tool names, with CEL expressions for fine-grained conditions. Teams can start with observability, then layer in approvals and deny rules without SDKs or invasive app changes.

Platforms Supported

Windows
Mac
Linux
Cloud
On-Premises
iPhone
iPad
Android
Chromebook

Platforms Supported

Windows
Mac
Linux
Cloud
On-Premises
iPhone
iPad
Android
Chromebook

Audience

Software developers, startups, and product teams that want a fast and scalable way to build and deploy AI agents inside their applications

Audience

Platform, DevEx, security, and operations teams that need to govern production AI agents, control tool access, approve risky actions, and maintain audit-ready visibility

Support

Phone Support
24/7 Live Support
Online

Support

Phone Support
24/7 Live Support
Online

API

Offers API

API

Offers API

Screenshots and Videos

Screenshots and Videos

Pricing

Free
Free Version
Free Trial

Pricing

$290 per month
Free Version
Free Trial

Reviews/Ratings

Overall 0.0 / 5
ease 0.0 / 5
features 0.0 / 5
design 0.0 / 5
support 0.0 / 5

This software hasn't been reviewed yet. Be the first to provide a review:

Review this Software

Reviews/Ratings

Overall 0.0 / 5
ease 0.0 / 5
features 0.0 / 5
design 0.0 / 5
support 0.0 / 5

This software hasn't been reviewed yet. Be the first to provide a review:

Review this Software

Training

Documentation
Webinars
Live Online
In Person

Training

Documentation
Webinars
Live Online
In Person

Company Information

21st.dev
21st.dev/

Company Information

Preloop
United States
preloop.ai/

Alternatives

Alternatives

Tuning Engines

Tuning Engines

CerebrixOS
AICtrlNet

AICtrlNet

Bodaty LLC
Spawn

Spawn

OpenRouter

Categories

Categories

Integrations

Amazon Bedrock
Claude Code
Cline
Codex CLI
Cursor
Gemini CLI
Hermes
Mattermost
Model Context Protocol (MCP)
OpenClaw
OpenCode
React
Slack
Tailwind CSS
Windsurf Browser
YAML
shadcn/ui

Integrations

Amazon Bedrock
Claude Code
Cline
Codex CLI
Cursor
Gemini CLI
Hermes
Mattermost
Model Context Protocol (MCP)
OpenClaw
OpenCode
React
Slack
Tailwind CSS
Windsurf Browser
YAML
shadcn/ui
Claim 21st and update features and information
Claim 21st and update features and information
Claim Preloop and update features and information
Claim Preloop and update features and information