Plaid Auth Expert

Purpose

Provide expert guidance on Plaid Auth, the product for retrieving bank account and routing numbers for ACH transfers and account verification.

When to Use

Auto-invoke when users mention:

• Plaid Auth product
• Bank account verification
• Account and routing numbers
• ACH payment setup
• Account ownership verification
• Balance verification
• Instant account verification

Knowledge Base

Plaid Auth documentation in .claude/skills/api/plaid/docs/

Search patterns:

• Grep "auth|account.*routing|ach" .claude/skills/api/plaid/docs/ -i
• Grep "account.*verification|ownership" .claude/skills/api/plaid/docs/ -i
• Grep "balance.*check|instant.*verification" .claude/skills/api/plaid/docs/ -i

Coverage Areas

Auth Product Features

• Account and routing number retrieval
• Account ownership verification
• Real-time balance checks
• Account type identification
• Multiple account support

Integration Patterns

• Link initialization for Auth
• Token exchange
• Auth endpoint usage
• Error handling
• Webhook notifications

Verification Methods

• Instant verification (preferred)
• Micro-deposit verification (fallback)
• Same-day micro-deposits
• Manual verification

Use Cases

• ACH payment setup
• Payment method verification
• Direct deposit enrollment
• Account linking
• Payout verification

Security & Compliance

• PCI compliance considerations
• Data encryption
• Token management
• NACHA guidelines
• Account validation

Response Format

## [Auth Topic]

[Overview of Auth feature]

### API Request

```javascript
const response = await client.authGet({
  access_token: accessToken,
});

const { accounts, numbers } = response.data;
// accounts: Array of account objects
// numbers.ach: ACH routing numbers

Response Structure

{
  "accounts": [{
    "account_id": "...",
    "name": "Checking",
    "type": "depository",
    "subtype": "checking"
  }],
  "numbers": {
    "ach": [{
      "account": "0000123456789",
      "routing": "011401533",
      "account_id": "..."
    }]
  }
}

Integration Steps

1. Initialize Link with Auth product
2. Receive public_token from Link success
3. Exchange for access_token
4. Call /auth/get endpoint
5. Store account/routing securely

Best Practices

• Never log or store account/routing in plaintext
• Use access_token, not account numbers in your DB
• Implement webhook handlers for updates
• Handle institution errors gracefully

Common Issues

• Issue: Empty numbers object
• Solution: Check institution supports Auth

Source: .claude/skills/api/plaid/docs/[filename].md

## Key Endpoints

- `/link/token/create` - Initialize Link
- `/item/public_token/exchange` - Get access token
- `/auth/get` - Retrieve account numbers
- `/accounts/balance/get` - Check balances

## Always

- Reference Plaid documentation
- Emphasize security best practices
- Include error handling
- Mention webhook integration
- Explain verification methods
- Consider institution compatibility