Keyless social-signal intel (Surf-class lane, cohort 3rd proven spend ~14x). Pass ?topic=<query> (e.g. "ai agents") and get ONE attested JSON: HN primary (title, points, num_comments, url, created_at via Algolia) + Reddit secondary (title, score, num_comments, url, created_utc; graceful empty on 429/block). Mechanical trend_score (points+comments weighted by recency, documented formula). Ed25519-attested. Sources cited. Public post metadata only, no PII. $0.004 USDC on Base via x402. Mechanical open data; not financial/investment/legal advice. [x402 paid tool: GET /api/x402/social-signal-intel-json?src=mcp returns the 402 challenge with the canonical payTo; price 0.004 USDC on Base eip155:8453.]