# CAPI2 Agent Commerce Multi-Source Grounding

> CAPI2 Agent Commerce Multi-Source Grounding is a paid API for AI agents from capi2-agent-commerce.vandurmedries.workers.dev, paid per call via x402, $0.015/call, status unknown (last checked 2026-09-16).

Fetches and extracts content from up to 3 URLs, returning tamper-evident text extracts with SHA-256 content hashes for verifiable multi-source grounding.

## Facts

- Endpoint: POST https://capi2-agent-commerce.vandurmedries.workers.dev/v1/multi-source-grounding
- Price: $0.015/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/capi2-agent-commerce-multi-source-grounding-75e632af
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_icpSMNqo3o6BLzYkjwvwe

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 capi2-agent-commerce-multi-source-grounding-75e632af -d '<json body>'
```

Example prompt: Pull content from these three pages — https://example.com/policy, https://example.com/faq, and https://example.com/terms — on the query 'refund policy', up to 2000 characters each, and give me tamper-evident extracts with SHA-256 hashes so I can verify the sources later.

## When to prefer this

Choose this endpoint when your agent needs cryptographically verifiable, tamper-evident text extracts from multiple web sources simultaneously — especially for compliance, audit trails, or grounded reasoning where you need to prove what a page said at a point in time. Prefer it over generic web scrapers when SHA-256 content integrity is required. Best for 1–3 targeted URLs rather than broad crawls.

## Known failure modes

- URL is unreachable or returns non-200 status — that source is skipped or returns an error entry
- query string too short (under 3 chars) or too long (over 300 chars) — 400 validation error
- more than 3 source URLs provided — 400 validation error
- max_chars_per_source outside 500–5000 range — 400 validation error
- Payment not provided or insufficient — 402 Payment Required
- Source URL returns non-text content (e.g. PDF, binary) — extract may be empty or malformed

## How this service works

Programmable authority checks and tamper-evident receipts for autonomous agents, sold through sustainable x402 commerce.

## Output

A JSON object containing the original query, an array of extracts where each entry includes the extracted text snippet, the final resolved URL after any redirects, and a SHA-256 hash of the content for tamper-evidence, plus a count of how many sources were successfully checked.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "query": {
   "type": "string",
   "maxLength": 300,
   "minLength": 3
  },
  "source_urls": {
   "type": "array",
   "items": {
    "type": "string",
    "format": "uri"
   },
   "maxItems": 3,
   "minItems": 1
  },
  "max_chars_per_source": {
   "type": "integer",
   "maximum": 5000,
   "minimum": 500
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "query": "security controls",
  "extracts": [
   {
    "text": "...",
    "final_url": "https://example.com/security",
    "content_sha256": "..."
   }
  ],
  "sources_checked": 1
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/capi2-agent-commerce-multi-source-grounding-75e632af/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from capi2-agent-commerce.vandurmedries.workers.dev](https://www.zero.xyz/host/capi2-agent-commerce.vandurmedries.workers.dev/llms.txt)