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Regex tester | agent view

The same page content and links, with explicit tool capabilities. Tools marked with an API can run directly through HTTP. Other tools require the browser interface or are not connected yet.

Tool capabilities

{
  "id": "regex-tester",
  "category": "developer-tools",
  "built": true,
  "requirements": "Declare JavaScript flavor and flags; show groups; interrupt pathological expressions.",
  "implementation": {
    "fields": [
      {
        "key": "pattern",
        "label": "Regular expression",
        "value": "\\b\\w+\\b",
        "type": "text"
      },
      {
        "key": "flags",
        "label": "Flags",
        "value": "g",
        "type": "text"
      }
    ],
    "note": "JavaScript regular expressions run in a disposable worker with a 1-second limit and maximum 10,000 matches.",
    "experience": {
      "automatic": false,
      "single": false,
      "label": "Your text",
      "placeholder": "Type or paste your input…",
      "help": "Up to 1,000,000 characters. Review the settings before running.",
      "action": null
    },
    "mode": "explicit",
    "interactive": false
  },
  "execution": "Browser interface",
  "api": null,
  "browser_agent": {
    "supported": true,
    "name": "run_current_tool",
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}

Page guide

Declare JavaScript flavor and flags.

Useful next steps

Find and replace

Replace every exact match with your chosen text.

Extract urls

Find unique HTTP and HTTPS links in pasted text.

JSON validator

Line/column errors and clear syntax-versus-schema validation scope.

How to use Regex tester

  1. Enter your text in the input field.
  2. Review the settings, then choose Run Regex tester.
  3. Review the result, then use Copy result or a download link when available.

Working with regex tester

Formatting makes existing data or code easier to read. Validation checks whether it follows a syntax or schema. Conversion maps it into another representation. Choosing the right operation helps avoid treating a neatly formatted result as proof that the underlying data is correct.

Common questions

Does valid JSON mean the data is correct?

Syntax validation only establishes that the text can be parsed as JSON. A schema can check required fields and types, but neither proves that an email address, price or external record is factually correct.

Is decoding the same as decrypting or verifying?

No. Base64 and URL encoding are representations, not encryption. Reading a token payload does not verify its signature. Use the specific validation or verification process required by the system receiving the result.

Continue your workflow: Find and replace, Extract urls, JSON validator.