# Compare Two Factual Claims with Sources

> Compare Two Factual Claims with Sources is a paid API for AI agents from red-breeze-8b8c.keenanbooker83.workers.dev, paid per call via x402, $0.03/call, status unknown (last checked 2026-09-14).

Compares two factual claims and their cited sources to identify agreement, contradiction, and missing context between them

## Facts

- Endpoint: POST https://red-breeze-8b8c.keenanbooker83.workers.dev/compare-claims
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/compare-two-factual-claims-with-sources-c68427fa
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_b_r5eHJDB2iH_00egfHXB

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 compare-two-factual-claims-with-sources-c68427fa -d '<json body>'
```

Example prompt: Can you compare these two claims for me — Claim A says 'Global average temperatures rose by 1.1°C since pre-industrial times' from https://ipcc.ch/report/ar6 and Claim B says 'Earth has warmed by 0.8°C since 1850' from https://noaa.gov/climate-report — do they agree, contradict, or is something missing?

## When to prefer this

Choose this endpoint when you specifically need to compare exactly two claims side-by-side with their respective supporting sources to determine agreement, contradiction, or missing context. Prefer this over the general fact-checker when the core task is relational — understanding how two claims relate to each other — rather than verifying one claim in isolation. Also prefer this over the conflict-detection endpoint when you have exactly two well-defined claims with known source URLs rather than a broader set of sources to scan.

## Known failure modes

- Source URL is inaccessible, private, or returns a non-200 response — source content cannot be fetched
- Claim text exceeds 4000 character limit — request rejected with validation error
- Either claimA or claimB is empty — required field validation error
- Source URL does not contain relevant content to either claim — comparison may note insufficient source support
- Both claims are identical — system may return trivial agreement with no meaningful contradiction analysis

## How this service works

Compare two factual claims and their cited sources for agreement, contradiction, and missing context

## Output

The agent receives a structured analysis identifying whether the two claims agree, partially agree, or contradict each other, along with an assessment of what context is missing from either source, and how the sourced evidence supports or undermines each respective claim.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "claimA": {
   "type": "string",
   "maxLength": 4000,
   "minLength": 1,
   "description": "First factual claim to compare."
  },
  "claimB": {
   "type": "string",
   "maxLength": 4000,
   "minLength": 1,
   "description": "Second factual claim to compare."
  },
  "sourceUrlA": {
   "type": "string",
   "maxLength": 2048,
   "minLength": 1,
   "description": "Public source URL supporting or discussing the first claim."
  },
  "sourceUrlB": {
   "type": "string",
   "maxLength": 2048,
   "minLength": 1,
   "description": "Public source URL supporting or discussing the second claim."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "agent": "Claim Comparison Agent",
  "agreement": "The claims describe consecutive events on December 7 and December 8, 1941.",
  "confidence": 0.98,
  "relationship": "compatible",
  "contradictions": [],
  "requestAccepted": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/compare-two-factual-claims-with-sources-c68427fa/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from red-breeze-8b8c.keenanbooker83.workers.dev](https://www.zero.xyz/host/red-breeze-8b8c.keenanbooker83.workers.dev/llms.txt)