Text word diff

text-word-diff · version 1.0.0 · Text · free, no key needed

Diff two texts as whitespace versus non-whitespace word tokens.

Use when you need to: text word diff · word token text diff · diff texts by words.

Supported

• text word diff
• word token text diff
• diff texts by words

Not supported

• locale word break
• Unicode UAX #29 word boundaries
• unicode normalization
• fuzzy matching
• patience/histogram diff
• treat U+00A0 as whitespace
• filesystem access

Behavior

• left and right are tokenized with splitWords: maximal runs of ASCII space, tab, CR, or LF versus maximal runs of everything else.
• U+00A0 is a word character, not whitespace. Empty text yields no tokens.
• The Myers SES uses string === equality; when D-paths tie, the library prefers delete from the left.
• ops is the per-token SES. keep includes left_index and right_index; delete includes left_index; insert includes right_index.
• keeps, deletions, and insertions count those op kinds. Adjacent keeps are not collapsed.
• Unknown input fields are rejected. Prototype-like tokens such as "__proto__" are ordinary strings.

Input

• left (string, required): max length 262144
• right (string, required): max length 262144

Output

• ops (array of object, required): max items 4096
• keeps (integer, required): min 0
• deletions (integer, required): min 0
• insertions (integer, required): min 0

Limits

• max text bytes: 262144
• max token count: 8192
• max edit ops: 4096
• max output bytes: 1048576

Example

Request input:

{
  "left": "ab cd",
  "right": "ab xy"
}

Response:

{
  "result": {
    "ops": [
      {
        "op": "keep",
        "value": "ab",
        "left_index": 0,
        "right_index": 0
      },
      {
        "op": "keep",
        "value": " ",
        "left_index": 1,
        "right_index": 1
      },
      {
        "op": "delete",
        "value": "cd",
        "left_index": 2
      },
      {
        "op": "insert",
        "value": "xy",
        "right_index": 2
      }
    ],
    "keeps": 2,
    "deletions": 1,
    "insertions": 1
  }
}

How to call it

MCP

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

{
  "id": "text-word-diff",
  "version": "1.0.0",
  "input": {
    "left": "ab cd",
    "right": "ab xy"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/text-word-diff/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"left":"ab cd","right":"ab xy"}'

The machine-readable contract is at /v1/tools/text-word-diff/versions/1.0.0.

CLI

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

Get the client at /clients/cli/.

Related tools

• Text line diff: Diff two texts as line records, preserving each line terminator.
• Text apply unified patch: Apply a one-file unified patch to text at original line addresses with exact hunk matches.
• Text diff stats: Summarize a line-record diff as keep, insert, delete, and hunk counts.
• Text invert unified patch: Invert a one-file unified patch by swapping file names and delete/insert ops.
• Text lines chunk: Split parsed lines into consecutive chunks of size lines each.
• Text parse unified patch: Parse a one-file unified patch into path names and 0-based hunks.