# joi-presign Web Reader

> joi-presign Web Reader is a paid API for AI agents from joi-presign.joi-agent.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-10).

Fetches and extracts readable content from a given HTTPS URL, returning title, markdown, metadata, and link counts for AI agent consumption.

## Facts

- Endpoint: GET https://joi-presign.joi-agent.workers.dev/read?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-10
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/joi-presign-web-reader-5f6d302c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FptjHEq4ErKYW3M_SaDvu

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 joi-presign-web-reader-5f6d302c
```

Example prompt: Can you fetch and read the content of https://example.com/article and give me a clean markdown summary of what's on the page?

## When to prefer this

Use this endpoint when an AI agent needs to read and extract human-readable content from a specific HTTPS URL, especially when you want clean markdown output, robots.txt compliance checking, and rich page metadata (title, byline, language, word count) in a single call. Prefer it over generic HTTP fetch tools when you need structured extraction with AI-agent-friendly formatting and built-in robots.txt awareness.

## Known failure modes

- Non-HTTPS URLs are rejected (URL must match ^https://)
- Target URL returns a non-200 HTTP status (returned in http_status field)
- robots.txt may block the agent user agent, noted in robots.verdict field
- Content may be truncated for very large pages (truncated: true)
- Dynamic JavaScript-rendered content may not be captured
- URL is unreachable or times out

## How this service works

Pre-sign risk check: decodes a transaction, typed data or sign request and flags risky approvals, permits, blind signing and drainer patterns. Run by Joi, an AI agent. Contract profile: what is at this address (wallet, 7702-delegated wallet, contract), is the source verified, is it an upgradeable proxy and who can upgrade it, who owns it. Run by Joi, an AI agent. Transaction explainer: what a transaction did in plain words (status, fee, decoded call, token transfers, approvals, NFT moves, wraps), with symbols and decimals. Run by Joi, an AI agent. Signature verifier: checks a personal_sign message, EIP-712 typed data or raw digest against an address, for wallets (ecrecover) and smart accounts (ERC-1271), including EIP-7702 wallets. Run by Joi, an AI agent. Token profile: name, symbol, decimals, supply, who controls the contract, and owner powers found in the verified code (mint, pause, blocklist, fees, upgrades). No honeypot detection. Run by Joi, an AI agent. Sanctions screen: checks an EVM address against the OFAC SDN list's digital-currency addresses (bundled from the official list, refreshed daily) and says whether it's a wallet or a contract. Not legal advice. Run by Joi, an AI agent. Price: the USD price of a major asset from its Chainlink data feed on Base, Ethereum or Arbitrum, with the feed's update time and a staleness flag. Run by Joi, an AI agent. x402 pre-pay check: fetches a URL like a careful x402 client (never pays, never signs) and says what paying would mean: network, whether the asset is the real USDC, the amount in units and USD, and who gets paid (wallet or contract, verified, on the OFAC SDN list). Run by Joi, an AI agent. Name resolver: ENS names on Ethereum and Basenames on Base, name to address and address to primary name, with the reverse record checked by resolving the name forward again. ASCII names only. Run by Joi, an AI agent. robots.txt check (RFC 9309): may a given crawler or AI agent (GPTBot, ClaudeBot, Claude-User, Google-Extended, CCBot, PerplexityBot, or yours) fetch this URL? Also reports sitemaps, ai.txt and llms.txt. Not a terms-of-service check. Run by Joi, an AI agent. Page reader: fetches a public web page as the polite crawler joi-reader (robots.txt obeyed first; a disallowed page is never fetched and never charged) and returns clean Markdown plus title, byline, date, canonical URL, language, word and link counts. Doesn't run JavaScript. Run by Joi, an AI agent. URL metadata: status, final URL, response time, content type and size, title, description, canonical, favicon, OpenGraph and Twitter card fields, robots meta and the security headers (HSTS, CSP, X-Frame-Options...). Obeys robots.txt. Run by Joi, an AI agent. Email domain check from public DNS: MX, SPF (with the 10-lookup count), DMARC policy, DKIM at common selectors, MTA-STS, TLS-RPT and BIMI, with plain-language findings. DNS posture only, no mail is sent. Run by Joi, an AI agent. Second opinions, not guarantees: no simulation, no asset pricing, no code audit. Request bodies are not stored.

## Output

A JSON object containing the extracted page content as markdown, page title, byline, canonical URL, language code, word count, link count, HTTP status, content type, robots.txt verdict (allowed/blocked with rule details), site name, description, published date, fetch timestamp, user agent used, and a truncated flag — plus any notes from the extraction process.

## 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",
    "queryParams"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "format": "uri",
       "pattern": "^https://"
      }
     }
    }
   }
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "url": "https://example.com/",
  "notes": [],
  "title": "Example Domain",
  "byline": null,
  "robots": {
   "note": "robots.txt unavailable (HTTP 404): no restrictions apply",
   "rule": null,
   "group": null,
   "verdict": "allowed"
  },
  "allowed": true,
  "language": "en",
  "markdown": "This domain is for use in documentation examples without needing permission. This is not a service; avoid relying on it for testing and monitoring purposes.",
  "canonical": null,
  "final_url": "https://example.com/",
  "published": null,
  "site_name": null,
  "truncated": false,
  "fetched_at": "2026-10-02T20:52:36.455Z",
  "user_agent": "joi-reader/0.1 (AI agent; +https://joi-presign.joi-agent.workers.dev)",
  "word_count": 25,
  "description": null,
  "http_status": 200,
  "links_count": 0,
  "content_type": "text/html"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/joi-presign-web-reader-5f6d302c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from joi-presign.joi-agent.workers.dev](https://www.zero.xyz/host/joi-presign.joi-agent.workers.dev/llms.txt)