Validation MCP Tools for AI Agents

Your chatbot agent accepts "user@.com" as a valid email because the LLM thought it "looked right." Validation requires precise rules, not vibes. These tools validate against actual RFC specifications and industry standards.

All Validation Tools (15)

Your agent gets access to 15 validation tools via the /mcp/validate/ endpoint. Here's the complete list:

Tool	Description
`validate/email`	Validate Email
`validate/url`	Validate Url
`validate/phone`	Validate Phone
`validate/credit-card`	Validate Credit Card
`validate/uuid`	Validate Uuid
`validate/ip`	Validate Ip
`validate/mac`	Validate Mac
`validate/json`	Validate Json
`validate/hex`	Validate Hex
`validate/base64`	Validate Base64
`validate/alphanumeric`	Validate Alphanumeric
`validate/password-strength`	Validate Password Strength
`validate/date`	Validate Date
`validate/domain`	Validate Domain
`validate/semver`	Validate Semver

Agent Scenarios

Here's how real agents use these tools:

1. Lead qualification agent

A sales agent validates prospect email addresses before adding them to CRM. validate/email checks RFC compliance and detects disposable domains.

Tool Call: validate/email

{ "email": "prospect@company.io" }

2. Payment processing agent

A checkout agent validates credit card numbers using Luhn algorithm before sending to payment gateway. validate/credit-card catches typos early.

Tool Call: validate/credit-card

{ "number": "4532015112830366" }

3. Form submission agent

A support agent validates phone numbers submitted in contact forms. validate/phone ensures proper formatting.

Tool Call: validate/phone

{ "phone": "+1-555-123-4567" }

MCP Setup

Add validation tools to your agent in under 2 minutes. Choose your client:

Claude Desktop / Claude Code

Add this to your MCP config:

{
  "mcpServers": {
    "tinyfn-validate": {
      "url": "https://api.tinyfn.io/mcp/validate/",
      "headers": {
        "X-API-Key": "your-api-key"
      }
    }
  }
}

Cursor

Go to Settings > MCP and add a new server:

Type: SSE
URL: https://api.tinyfn.io/mcp/validate/sse
Headers: X-API-Key: your-api-key

Tip: Use the category-specific endpoint (/mcp/validate/) for the best experience. The all-in-one endpoint (/mcp/all/) works too but has 500+ tools which some clients handle less efficiently.

When to Use These Tools

Use validation MCP tools when your agent needs to:

Guarantee correctness — when wrong answers have real consequences
Process user data — when you're operating on actual user input, not hypothetical examples
Maintain consistency — when the same input must always produce the same output

You don't need these tools for casual conversation or rough estimates. Use them when precision matters.

Ready to add validation tools to your agent?

Get Free API Key 100 requests/month free. No credit card required.

Frequently Asked Questions

Why shouldn't LLMs handle validation?

LLMs learn validation patterns from training data, which may include incorrect or outdated rules. They can't reliably apply complex specifications like RFC 5322 for email validation or the Luhn algorithm for credit cards.

What validation types does TinyFn support?

TinyFn validates emails, URLs, phone numbers, credit cards, UUIDs, ISBNs, IP addresses, JSON, semver versions, and more.

Do validation tools return detailed error information?

Yes. Each validation tool returns structured results including validity status, specific error reasons, and parsed components where applicable.