{"product": "belief-half-life-fact-expiry-ledger", "name": "Belief Half-Life: Fact-Expiry Ledger for Agents", "provider": "TextForAgents LLC", "support": "support@textforagents.com", "what": "Stamps each retrieved fact with a signed provenance stamp (value hash, source, decay class, born_at, hops), fits its half-life from the source's observed change intervals, and answers FRESH / STALE / EXPIRED scaled by action irreversibility (draft 2.0 / standard 1.0 / irreversible 0.5 half-lives). Age survives compaction, handoff and hibernation; stripped stamp = UNKNOWN-AGE, forged = INVALID, never FRESH.", "prices": {"per_check_usd": 0.005, "receipt_usd": 0.01, "fleet_usd_per_month_per_agent": 9, "fleet_includes": "up to 1,000 tracked facts per agent: stamp issuance, ledger storage, scheduled force-refresh sweeps, checks against own tracked facts"}, "trial": "First 100 freshness checks free, once per operator account (account and payer wallet enforced). Receipts are $0.01 each via x402 at all times - not part of the trial grant or the fleet tier. No perpetual free tier.", "limits": ["Request bodies capped at 64KB (413).", "Unknown action class is refused (400), never defaulted.", "A verdict does not warrant that a fact has not changed inside its allowance: within-allowance change floor 7.9% standard / 4.7% irreversible on the n=4,000 retrospective.", "Refresh re-queries are never bundled flat: on STALE/EXPIRED the verdict is returned and refresh is the customer's own retrieval or a metered x402 pass-through.", "Half-lives below 3 observations are labeled priors, never presented as fitted."], "how_to_start": ["POST /register {account_name, payer_wallet} -> token (shown once).", "POST /register with Bearer token {fact_key, source, fact_class, value} -> signed stamp.", "POST /check with Bearer token {stamp, action_class} -> verdict (trial, then x402 $0.005).", "POST /handoff, POST /receipt, POST /subscribe ($9 fleet) as documented in /openapi.json."], "docs": "/openapi.json", "llms": "/llms.txt", "terms": "/terms", "privacy": "/privacy"}