# Diff Lines Text Comparison Tool

> Diff Lines Text Comparison Tool is a paid API for AI agents from gpt55.558686.xyz, paid per call via x402, $0.0001/call, status unknown (last checked 2026-09-15).

Compares two multi-line text strings line-by-line and returns a diff summary, paid via x402 USDC microtransaction.

## Facts

- Endpoint: GET https://gpt55.558686.xyz/v1/tools/diff-lines
- Price: $0.0001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/diff-lines-text-comparison-tool-b5d121e7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_AXgSo-uYzFEyYEea-WI2S

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 diff-lines-text-comparison-tool-b5d121e7
```

Example prompt: Compare these two versions of my config file line by line and tell me what changed — before: 'host=localhost\nport=8080\ndebug=true' and after: 'host=prod.example.com\nport=443\ndebug=false'.

## When to prefer this

Use this endpoint when you need a quick, pay-per-use line-by-line text diff without a subscription, especially when integrating into an agent workflow that already supports x402 USDC micropayments on Base. Prefer this over general-purpose LLM prompts for structured diff output.

## Known failure modes

- Missing 'before' or 'after' query parameter returns an error
- Text inputs exceeding 50,000 characters are rejected
- Payment failure via x402 USDC results in 402 response and no result
- Invalid query parameter types may cause schema validation errors
- Network or gateway timeout for very large diffs

## How this service works

Compare two newline-separated text blocks and return added, removed, and unchanged line sets without calling an upstream model. Pay up to $0.001 per request with x402 USDC on Base. Public paid calls are limited to 1500 input characters and 128 output tokens.

## Output

A JSON object with ok: true, tool: 'diffLines', and a summary describing the line-level differences between the before and after text inputs. Identifies added, removed, and unchanged lines.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "additionalProperties": true
    },
    "queryParams": {
     "type": "object",
     "required": [
      "before",
      "after"
     ],
     "properties": {
      "after": {
       "type": "string",
       "maxLength": 50000
      },
      "before": {
       "type": "string",
       "maxLength": 50000
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "tool": {
       "type": "string"
      },
      "fetchedAt": {
       "type": "string"
      }
     },
     "additionalProperties": true
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/diff-lines-text-comparison-tool-b5d121e7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from gpt55.558686.xyz](https://www.zero.xyz/host/gpt55.558686.xyz/llms.txt)