Text control characters find

text-control-characters-find · version 1.0.0 · Text · free, no key needed

Find non-whitespace control characters in a text string.

Use when you need to: text control characters find · find control characters · detect non-printable characters.

Supported

• text control characters find
• find control characters
• detect non-printable characters

Not supported

• remove control characters
• check whitespace
• read files

Behavior

• Control characters are defined as Unicode code points in the ranges U+0000-U+001F and U+007F-U+009F.
• Standard whitespace control characters (U+0009 Tab, U+000A LF, U+000D CR) are ignored.
• Returns up to 1000 matches, containing the 0-based UTF-16 code unit offset (index) and the code point as a hex string (e.g., "U+001B").
• Note: index represents the UTF-16 code unit offset in JavaScript strings, which may diverge from code point offset in strings containing astral characters/surrogate pairs.

Input

• text (string, required): max length 1048576

Output

• matches (array of object, required)

Limits

• max text bytes: 1048576

Example

Request input:

{
  "text": "hello\u001bworld\u0000"
}

Response:

{
  "result": {
    "matches": [
      {
        "index": 5,
        "code_point": "U+001B"
      },
      {
        "index": 11,
        "code_point": "U+0000"
      }
    ]
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "text-control-characters-find",
  "version": "1.0.0",
  "input": {
    "text": "hello\u001bworld\u0000"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/text-control-characters-find/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"text":"hello\u001bworld\u0000"}'

The machine-readable contract is at /v1/tools/text-control-characters-find/versions/1.0.0.

CLI

node cli.mjs run text-control-characters-find 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

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• Text conflict render: Render text and conflict parts as merge or diff3 conflict-marker text.
• Text count: Count Unicode code points, UTF-16 code units, UTF-8 bytes, and lines.
• Text diff stats: Summarize a line-record diff as keep, insert, delete, and hunk counts.