The API Layer Built for AI Agents.
One Key. Every Tool.

Give your AI agents one key — and instant access to 184+ APIs. No wiring. No credentials sprawl. Just ship.

Get Started Book a Demo

184

Integrations Available

AES-256

Encrypted BYOK Storage

< 150ms

Routing Overhead Latency

Universal

MCP & HTTP Endpoints

Connect any tool or application with Callio

Stripe

Payments

Slack

Chat

GitHub

Dev

Google Search

Web search

OpenAI GPT-4o

LLM

SendGrid

Email send

Anthropic Claude

Agent reasoning

Google Maps

Locations

Stripe

Payments

Slack

Chat

GitHub

Dev

Google Search

Web search

OpenAI GPT-4o

LLM

SendGrid

Email send

Anthropic Claude

Agent reasoning

Google Maps

Locations

Google Calendar

Meetings

Twilio SMS

SMS logs

Resend

Modern email

Supabase PG

Database

Pinecone Db

Vector search

Linear

Tickets

Shopify Store

Commerce

Apify Scraper

Web extraction

Google Calendar

Meetings

Twilio SMS

SMS logs

Resend

Modern email

Supabase PG

Database

Pinecone Db

Vector search

Linear

Tickets

Shopify Store

Commerce

Apify Scraper

Web extraction

Orchestrate API requests from any Agent

Choose an upstream target provider API below and trace how the Callio Gateway maps keys, processes headers, and forwards calls.

Sources (AI Stack)

Cursor MCP

Agentic IDE tool calls

Python / Node SDK

Standard backend scripts

Claude Desktop

MCP environment integration

Callio Hub

BYOK Active

Single Gateway handles auth injection, rates, & SSL.

Targets (Unified Proxy)

gateway proxy inspector

https://api.callio.dev/v1/proxy/slack/chat.postMessage

Outgoing Proxy RequestPOST

> Host: api.callio.dev

> Authorization: Bearer callio_live_••••••••

> X-Upstream-Key: injected_by_callio

> Content-Type: application/json

{
  "channel": "#ops-alerts",
  "text": "🟢 Agent task completed in 420ms"
}

Upstream Provider Response200 OK

< HTTP/1.1 200 OK

< Content-Type: application/json

< X-Callio-Time: 128ms

< X-Callio-Quota: 2,341/10,000

{
  "ok": true,
  "channel": "C03248",
  "ts": "1778796622.04",
  "message": {
    "text": "🟢 Agent task completed in 420ms",
    "type": "message"
  }
}

Developer SDKs & Configurations

Plugs natively into your stack

Callio is build-agnostic. Drop the server into your Cursor config, add it as a Claude desktop tool, or import our Python and JavaScript SDKs. One single API key powers everything.

Works with any agent framework or orchestration layer.

Bring Your Own Keys (BYOK) loaded on the dashboard.

SSL secure routing with auto-retries on 5xx errors.

Read the API documentation

.cursor/mcp.json

{
  "mcpServers": {
    "callio": {
      "command": "npx",
      "args": ["-y", "github:hmadhsan/callio-mcp"],
      "env": {
        "CALLIO_API_KEY": "callio_your_api_key"
      }
    }
  }
}

Engineered for agent safety & speed

Callio is built with production reliability at its core, keeping your credentials secure and operations running.

Secure Credentials (BYOK)

Bring your own keys. Credentials are stored using AES-256-GCM encryption at rest and injected dynamically at the proxy layer.

Zero-Data Logging

We value privacy. Request and response bodies are streamed through callio without ever touching disk or application logs.

Automatic Retries & Limits

Failures are resolved dynamically. Callio retries upstream 5xx errors and throttles requests with per-key sliding rate limits.

Aggregated Observability

Gain instant visibility. Run analytics, count usage metrics, and inspect transaction latency inside your Callio dashboard.

Full tracing across all provider endpoints

Callio monitors proxy operations, capturing request methods, providers, speeds, and payload weights automatically.

CallioLogs Real-Time Observability

Listening

SSL secure proxies. Zero-body payload logging.Filter: * (All requests)

Frequently Asked Questions

Everything you need to know about Callio's features and infrastructure.

What is Callio?

Callio is the high-performance unified API gateway for AI agents and LLM applications. One key and one endpoint lets your agent securely interface with 184+ external APIs without SDK bloat.

How is Callio different from standard API clients?

Instead of spending hours writing auth boilerplate, configuring custom headers, handling rate-limits, and routing logs for every provider, you connect your agent to Callio. We handle credentials injection, retry logic, timeout termination, and trace logging out of the box.

How does the Model Context Protocol (MCP) work?

Callio runs a compliant MCP server. Drop our command config into Cursor, Claude Desktop, Claude Code, or Antigravity, and your AI assistant immediately inherits tool calls for all 184 APIs using your single Callio key. View setup details.

Are my provider API credentials safe with Callio?

Absolutely. We enforce bank-grade security. All provider credentials (BYOK) are encrypted at rest using AES-256-GCM. Furthermore, Callio is zero-data logging: we pass through payload bodies and only store metadata (status, latency) for your dashboard.

How do I start and what are the pricing plans?

Our sandbox plan is free forever and includes 500 requests to help you test integrations. Production plans start at $19/month for builder workloads. Check our pricing table for limits.

Ready to scale your agent integrations?

Create an account, grab a single API key, and connect to over 184 tools in minutes. Start testing for free on our sandbox plan.