# agentread /compare

> agentread /compare is a paid API for AI agents from agentread.midi-thumb.workers.dev, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-31).

Compares two fetched versions of a URL and returns a diff summary showing what content was added or removed between them.

## Facts

- Endpoint: POST https://agentread.midi-thumb.workers.dev/compare?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentread-compare-a7ecf94c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__pIs16nmHGBB08rZB_Gkx

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 agentread-compare-a7ecf94c -d '<json body>'
```

Example prompt: I fetched that product page twice and something changed — can you compare the two versions and tell me what was added or removed?

## When to prefer this

Use this endpoint when you need to compare two fetched states of a webpage that your own HTTP client struggled to retrieve, particularly for pages behind 403/429 guards, JavaScript shells, or anti-bot measures. Prefer it over generic diff utilities when the target URL is a live web page requiring special fetch handling.

## Known failure modes

- URL unreachable or blocked — returns a verdict string explaining the access failure
- Invalid or missing 'input' object — returns a 400-level error
- Both fetches return empty bodies due to JS rendering — diff may show 0 changes incorrectly
- Payment not included or insufficient — returns 402 requiring $0.02 USDC via x402

## How this service works

Read a URL your own fetch failed on and get the page text back, or a verdict explaining why it cannot be read. Built for agents that just got a 403, 429, empty body or JS shell.

## Output

A JSON object with a 'same' boolean indicating whether the two pages are identical, an 'added_count' integer for newly added content blocks, and a 'removed_count' integer for removed content blocks. On failure, returns a verdict explaining why the comparison could not be completed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "const": "http"
    },
    "method": {
     "const": "POST"
    }
   },
   "additionalProperties": true
  },
  "output": {
   "type": "object",
   "additionalProperties": true
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "same": false,
  "added_count": 2,
  "removed_count": 1
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentread-compare-a7ecf94c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentread.midi-thumb.workers.dev](https://www.zero.xyz/host/agentread.midi-thumb.workers.dev/llms.txt)