Regex Generator

Describe what to match in plain English and get a tested regular expression, checked against your examples if you give them.

Pay by wallet (x402) AI-generated regex-generate

Example

Input

{
  "description": "This is a test input for automated capability testing."
}

Answer

{
  "flags": "g",
  "regex": "This is a test input for automated capability testing\\.",
  "explanation": "Matches the literal string 'This is a test input for automated capability testing.' - 'This is a test input for automated capability testing' matches the exact phrase, and '\\.' matches the literal period at the end. The 'g' flag finds all occurrences.",
  "test_results": [
    {
      "input": "This is a test input for automated capability testing.",
      "match": "This is a test input for automated capability testing.",
      "matches": true
    },
    {
      "input": "This is a test input for automated capability testing",
      "match": null,
      "matches": false
    },
    {
      "input": "this is a test input for automated capability testing.",
      "match": null,
      "matches": false
    },
    {
      "input": "This is a test input for automated capability testing. This is a test input for automated capability testing.",
      "match": "This is a test input for automated capability testing.",
      "matches": true
    }
  ]
}

Inputs

Field	Type	Required	What it is
`description`	string	Yes	What to match in natural language
`test_strings`	array	No	Optional strings to test against

Output fields

How reliably each field appears in a successful answer.

Field	Type	Appears
`flags`	string	Always (present in every successful answer)
`regex`	string	Always (present in every successful answer)
`explanation`	string	Always (present in every successful answer)
`test_results`	array	Always (present in every successful answer)

How to call it

The same tool through each route. MCP clients reach it through Strale’s server at https://api.strale.io/mcp; the call below is what the agent sends.

# Needs an API key. max_price_cents caps what this call may cost.
curl -X POST https://api.strale.io/v1/do \
  -H "Authorization: Bearer $STRALE_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
    "capability_slug": "regex-generate",
    "inputs": {
      "description": "This is a test input for automated capability testing."
    },
    "max_price_cents": 5
  }'

{
  "tool": "strale_execute",
  "arguments": {
    "slug": "regex-generate",
    "inputs": {
      "description": "This is a test input for automated capability testing."
    },
    "max_price_cents": 5
  }
}

import { Strale } from "straleio";

const strale = new Strale({ apiKey: process.env.STRALE_API_KEY! });
const result = await strale.do({
  capability_slug: "regex-generate",
  inputs: {
    "description": "This is a test input for automated capability testing."
  },
  max_price_cents: 5,
});

import os
from straleio import Strale, DoRequest

strale = Strale(api_key=os.environ["STRALE_API_KEY"])
result = strale.do(DoRequest(
    capability_slug="regex-generate",
    inputs={
        "description": "This is a test input for automated capability testing.",
    },
    max_price_cents=5,
))

# No account. The first request answers 402 with the price in USDC;
# an x402 client pays it from your wallet and repeats the request.
curl -i 'https://api.strale.io/x402/v2/regex-generate?description=This+is+a+test+input+for+automated+capability+testing.'

Limitations

Complex patterns need testing and refinement
AI-generated regex — complex patterns with edge cases may need refinement and testing against your full dataset
What to do instead: Test the generated regex against both matching and non-matching examples before deploying in production
Output size cap per call
Structured output is limited to about 800 output tokens per call; requests exceeding this limit are refused rather than returned truncated. The `test_strings` array has no input-count cap, but each string adds a test result that can exceed the output limit; an identical retry does not help.
What to do instead: Provide fewer test_strings per call

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