Regex Tester API
  
Test regex patterns against strings. Get all matches, capture groups, positions, and plain-English pattern explanations. Pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.
Part of the klymax402 marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.
Quickstart -- MCP
Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):
{
"mcpServers": {
"regex-generator": {
"url": "https://regex-generator.api.klymax402.com/mcp"
}
}
}
Quickstart -- HTTP (x402)
curl -X POST "https://regex-generator.api.klymax402.com/api/test" \
-H "Content-Type: application/json" \
-d '{"pattern":"...","testStrings":"..."}'
# -> 402 Payment Required, with an x402 payment challenge in the response body
Any x402-aware client (@x402/fetch, x402-agent-tools, ATXP) handles the 402 -> sign -> retry cycle automatically.
Tools
| Tool | Method | Path | Price | Description | |---|---|---|---|---| | text_test_regex | POST | /api/test | $0.003 | Test a regex pattern against input strings |
text_test_regex
Use this when you need to test a regular expression against one or more strings. Returns all matches, capture groups, positions, and a human-readable explanation of the pattern.
Parameters
| Name | Type | Required | Description | |---|---|---|---| | pattern | string | yes | Regular expression pattern (without delimiters) | | flags | string | no | Regex flags: g, i, m, s, u (default: g) | | testStrings | array | yes | Array of strings to test against the pattern |
Example response:
{"pattern":"\d{3}-\d{4}","flags":"g","explanation":"Matches 3 digits, a hyphen, then 4 digits","results":[{"input":"Call 555-1234","matched":true,"matches":[{"value":"555-1234","index":5,"groups":[]}]}],"totalMatches":1}
When to use: validating regex patterns before deploying them in code, debugging why a pattern fails to match, or extracting structured data from text. Use this BEFORE writing complex regex into production code.
Not for: text classification (use text_classify_content), PII detection (use privacy_detect_pii), text comparison (use text_compare_diff).
Example agent prompts
- "Test a regular expression against one or more strings"
Payment
- Protocol: x402 -- HTTP-native pay-per-call, no signup, no API key
- Network: Base L2 (
eip155:8453) - Asset: USDC
- Facilitator: Coinbase CDP (primary), PayAI (fallback)
- Also reachable via ATXP (OAuth-wrapped x402, RFC 9728 protected-resource metadata)
Part of klymax402
100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.
- Catalog: https://klymax402.com/llms.txt
- Full API reference: https://klymax402.com/llms-full.txt
- Live stats: https://klymax402.com/stats
License
MIT











