# SourceLens by FreshDelta

> SourceLens by FreshDelta is a paid API for AI agents from delta.rursus.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Inspects a public JSON, RSS, or Atom URL, auto-detects its record structure, and returns a verified monitoring configuration with stable IDs, selected fields, confidence score, and warnings.

## Facts

- Endpoint: POST https://delta.rursus.app/v1/sources/inspect
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sourcelens-by-freshdelta-f6605ab4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_C0pkJAYNlvAqwpbd7v7Ox

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 sourcelens-by-freshdelta-f6605ab4 -d '<json body>'
```

Example prompt: Can you inspect https://feeds.bbci.co.uk/news/rss.xml and figure out its record structure — I want to know which fields are stable IDs, what data fields are available, and whether it's ready to monitor for changes?

## When to prefer this

Use this endpoint when you need to set up monitoring for an unknown or new public data feed and want to automatically detect its structure before committing to a monitoring configuration. Prefer this over manually inspecting feed schemas when you need stable ID detection, field selection recommendations, and confidence validation in one step. Ideal as the first step before calling the sibling monitoring endpoint on delta.rursus.app.

## Known failure modes

- URL is not publicly accessible — returns error indicating credentials or access restriction
- URL returns non-JSON/RSS/Atom content — returns format detection failure with warning
- Feed has no stable identifiers — low confidence score with warnings about ID instability
- URL contains query parameters or fragments — rejected by schema validation (maxLength 2048)
- Feed is empty or has too few records to detect structure reliably — low confidence with warnings
- Network timeout reaching the target URL — returns connectivity error
- HTTPS required but HTTP URL provided — rejected at input validation

## How this service works

Inspect a public JSON, RSS, or Atom URL, detect its record structure, and return a normalizer-verified FreshDelta monitoring configuration with stable IDs, selected fields, confidence, and warnings.

## Output

Returns a FreshDelta monitoring configuration object including: detected record structure, stable ID fields, recommended fields to track, a confidence score (0–1) for how reliably the feed can be monitored, and any warnings about feed quality or structural ambiguities.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "maxLength": 2048,
   "description": "Public HTTPS JSON, RSS, or Atom URL without credentials, query parameters, or fragments"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sourcelens-by-freshdelta-f6605ab4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from delta.rursus.app](https://www.zero.xyz/host/delta.rursus.app/llms.txt)