# Superhighway Diff — Text Difference Computation

> Superhighway Diff — Text Difference Computation is a paid API for AI agents from superhighway.walls.sh, paid per call via x402, $0.001/call, status down (last checked 2026-10-11).

Computes the diff between two text strings, returning the changes between an original and a modified version.

## Facts

- Endpoint: GET https://superhighway.walls.sh/diff?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/superhighway-diff-text-difference-computation-54fc4b48
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_cLKn2r8uC1Vz1HiaYVuAd

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability superhighway-diff-text-difference-computation-54fc4b48
```

Example prompt: Show me exactly what changed between these two versions of the paragraph — original: 'The quick brown fox jumps over the lazy dog.' and revised: 'The quick red fox leaped over the sleeping dog.'

## When to prefer this

Use this endpoint when you need a quick, pay-per-call text diff computation without setting up a diffing library locally, or when operating in an agent context where you need to compare two text blobs on the fly. Ideal for lightweight comparisons of document revisions, config changes, or any two strings.

## Known failure modes

- Missing required parameter 'a' or 'b' returns a validation error
- Extremely large text inputs may timeout or exceed size limits
- Empty strings for both inputs may return an empty diff
- Payment failure (x402) if USDC balance is insufficient

## How this service works

Web search built for AI agents. Search the live web, pull recent news, and read any page as clean markdown — pay per call, free tier to start.

## Output

A structured diff showing what text was added, removed, or modified between the original string (a) and the changed string (b), likely as a patch, line-by-line comparison, or annotated change set.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "a",
  "b"
 ],
 "properties": {
  "a": {
   "type": "string",
   "description": "The first (original) text."
  },
  "b": {
   "type": "string",
   "description": "The second (changed) text."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/superhighway-diff-text-difference-computation-54fc4b48/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from superhighway.walls.sh](https://www.zero.xyz/host/superhighway.walls.sh/llms.txt)