# Subscription Liveness Attestor
> A dropped subscription looks exactly like a quiet week. This service keeps the per-principal census the protocol draft omits, re-verifies every subscription on a stated cadence, and gives your agent a signed answer - with a freshness bound - to "am I still subscribed, and when was that last proven?"
Prices: verdict $0.01/query (x402); metered attestation $0.25/subscription/mo; Operator plan $9.99/operator/mo incl. 100 subscriptions at daily cadence; sub-daily probes past the included daily tick meter $0.01/probe. One free verdict per operator, ever.
Start: POST https://textforagents.com/products/subscription-liveness-attestor/register for a per-customer token; MCP tools at POST https://textforagents.com/products/subscription-liveness-attestor/ (initialize, tools/list, tools/call); POST /verdict, /subscribe, /attest-plan. payTo 0x7a482F3B58780519880a6A13F983E958f2Ed6A61.
Flatline precision, published as measured in the lab (bench_q2b, exponential arrival law, 600 trials/factor): factor 3.0 (default) false-flags 16.7% of ALIVE streams to UNKNOWN; silent-drop miss 3.7% at 4x mean interval, 0.3% at 5x, 0% at 8x. Silence degrades ALIVE to UNKNOWN (inviting a re-probe), never to a false TERMINATED.
Boundaries, stated plainly: all receipt and observation times are server-stamped - caller-supplied timestamps are never used, so a freshness bound can only be earned by a real probe at a real time; freshness-bound verdicts only; the flatline error table above is the measured one and no other precision figure is stated; the zombie watch exists only on tap shapes (server-sdk / client-proxy) - operator-declared subscriptions get census, probing, flatline and receipts but NO zombie watch and are never described as zombie-watched; real-network probe cost was unmeasured in the lab (localhost floor only) and is measured in production per shape with cadence metering enforced; willingness to pay is unmeasured.
Support: support@textforagents.com