# Arcjet

A security SDK plus cloud decision API that you call from your own code (JS/TS, Python, Go) to rate-limit, block bots, validate emails, run a WAF, detect prompt injection and redact PII, with hooks to allow or block coding-agent and MCP tool calls.

- Category: App and agent security · by Arcjet Labs, Inc.
- Website: https://arcjet.com/
- Live data: no
- Checked on the official pages: 2026-10-24

## API

- Official API: yes, docs https://docs.arcjet.com/
- Key needed: yes
- Price: Free tier; limits: Free plan after the 15-day trial: 10,000 requests per month, hard stop; paid usage $5 per 1M web requests, $50 per 1M agent requests
- Formats: json

## Price and code

- Free tier: 15-day trial, then a free plan limited to 10,000 requests per month (hard stop); paid from $25/month (https://arcjet.com/pricing)

## Data and license

- License: Arcjet Terms of Service (https://arcjet.com/terms); covers Use of the hosted service for personal use or internal business purposes; SDK source is Apache-2.0
- Commercial use with conditions
- Credit: not stated
- Embedding unclear
- Quote (api_official): "Native SDKs for JavaScript, TypeScript, Python, and Go protect services, queues, jobs, and workflow steps – not only HTTP handlers." (https://arcjet.com/llms.txt)
- Quote (api_key): "ARCJET_KEY=ajkey_yourkey" (https://docs.arcjet.com/llms-full.txt)
- Quote (free_tier): "Free plan: after the 15-day trial, accounts continue on a free plan limited to 10,000 requests per month. The limit is a hard stop rather than metered overage." (https://arcjet.com/llms.txt)
- Quote (paid_from): "Individual Get started. $ 25 / mo Start a 15 day trial 1 team member 1 hour log retention Email support" (https://arcjet.com/pricing)
- Quote (api_price): "Web Requests Protecting websites and web apps with bot protection, Shield WAF, email validation, etc. $5 per 1M requests Agent Requests Protecting coding agents and custom agents with PII detection, prompt injection protection, tool guards, etc. $50 per 1M requests" (https://arcjet.com/pricing)
- Quote (commercial): "you are hereby granted a non-exclusive, limited, non-transferable, and freely revocable license to access and use the Service, solely for your personal use or internal business purposes" (https://arcjet.com/terms)
- Quote (maker): "provided by Arcjet Labs, Inc. (including its successors and assigns, “ Arcjet ,” “ we ,” “ our ,” or “ us ”)" (https://arcjet.com/terms)
- Quote (mcp): "same management surface over MCP at `https://api.arcjet.com/mcp` (OAuth)." (https://arcjet.com/llms.txt)

## Rules for an agent

- Install the framework SDK (e.g. npm i @arcjet/next or @arcjet/node, pip install arcjet, go get github.com/arcjet/arcjet-go) and set ARCJET_KEY; skills via `npx skills add arcjet/skills`; management MCP at https://api.arcjet.com/mcp uses OAuth; full docs at https://docs.arcjet.com/llms-full.txt.
- Keep ARCJET_KEY in environment variables, not source control
- Free plan stops protecting at 10,000 requests/month; plan for that limit in production
- Hosted service is licensed for your own internal business use; no reselling

## Agent access

- llms.txt: https://arcjet.com/llms.txt
- MCP: https://api.arcjet.com/mcp

Human page: https://agentgid.com/resources/arcjet/
Source: AgentGid (agentgid.com). Facts are quoted from the site's own pages; check the license page before you ship.