# Services from penny-army-reference-mainnet.spruceboundgranitestudio.workers.dev on Zero

> penny-army-reference-mainnet.spruceboundgranitestudio.workers.dev serves 5 paid API services for AI agents, indexed by Zero. Each is callable per call with payment handled by Zero.

Canonical page: https://www.zero.xyz/host/penny-army-reference-mainnet.spruceboundgranitestudio.workers.dev
Live health (JSON, refreshed every minute): https://www.zero.xyz/host/penny-army-reference-mainnet.spruceboundgranitestudio.workers.dev/health.json

## Services

- [Penny Army Reference Metadata Comparator](https://www.zero.xyz/c/penny-army-reference-metadata-comparator-9927ce0e/llms.txt): $0.05/call via x402. Compares up to 10 DOI-bearing academic references against Crossref metadata, returning field-level agreements, discrepancies, and ambiguities for title, authors, and year.
- [Penny Army Column Completeness Probe](https://www.zero.xyz/c/penny-army-column-completeness-probe-c5424eb8/llms.txt): $0.05/call via x402. Analyzes JSON records to classify each specified field as absent (missing key), explicitly null, blank string, or populated, across a batch of rows.
- [Penny Army JSON Merge Patch](https://www.zero.xyz/c/penny-army-json-merge-patch-0e470271/llms.txt): $0.001/call via x402. Applies an RFC 7396 JSON merge patch to a target JSON object using own-property-safe object construction, without storing or mutating any persisted data.
- [Penny Army Research – Robots.txt Directives Inspector](https://www.zero.xyz/c/penny-army-research-robots-txt-directives-inspector-d41e2297/llms.txt): $0.001/call via x402. Parses and inventories robots.txt content to enumerate user-agent groups, literal rule strings, and sitemap declarations without fetching URLs or evaluating permissions.
- [Penny Army Research – Redact Fields](https://www.zero.xyz/c/penny-army-research-redact-fields-1904702b/llms.txt): $0.001/call via x402. Recursively replaces values at exactly named object keys throughout a JSON payload, enabling field-level redaction by key name.

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

- [Zero catalog index](https://www.zero.xyz/llms.txt)