Text extract between

text-extract-between · version 1.0.0 · Text · free, no key needed

Extract exact substrings between start and end markers, left to right and non-overlapping.

Use when you need to: text extract between · extract text between markers · substring between start and end markers.

Supported

• text extract between
• extract text between markers
• substring between start and end markers

Not supported

• regular expressions
• nested or balanced delimiters
• case-insensitive search
• overlapping matches
• grapheme cluster matching
• read files

Behavior

• text is a UTF-8 bounded string of at most 250 KiB. Empty text yields matches [] and truncated false.
• start and end are non-empty literal strings of at most 4096 UTF-8 bytes. They may be equal.
• Search is exact UTF-16 code-unit equality, left to right, without regex, case folding, or Unicode normalization.
• After a complete match, search continues after the end marker so matches never overlap. Nested markers inside a match are not treated as new starts.
• If start equals end, each pair of consecutive occurrences yields the contents between them, which may be empty.
• If a start marker is found and no end marker follows it, the tool throws unclosed start marker.
• max_matches is a JSON integer 1..1000 and defaults to 100. At most that many matches are returned.
• truncated is true when at least one further complete match exists after max_matches were collected; exceeding the cap does not throw.

Input

• text (string, required): max length 256000
• start (string, required): min length 1; max length 4096
• end (string, required): min length 1; max length 4096
• max_matches (integer, optional): min 1; max 1000

Output

• matches (array of string, required): max items 1000
• truncated (boolean, required)

Limits

• max text bytes: 256000
• max marker bytes: 4096
• default max matches: 100
• max matches: 1000

Example

Request input:

{
  "text": "pre[one]mid[two]post",
  "start": "[",
  "end": "]"
}

Response:

{
  "result": {
    "matches": [
      "one",
      "two"
    ],
    "truncated": false
  }
}

How to call it

MCP

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

{
  "id": "text-extract-between",
  "version": "1.0.0",
  "input": {
    "text": "pre[one]mid[two]post",
    "start": "[",
    "end": "]"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/text-extract-between/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"text":"pre[one]mid[two]post","start":"[","end":"]"}'

The machine-readable contract is at /v1/tools/text-extract-between/versions/1.0.0.

CLI

node cli.mjs run text-extract-between 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

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