{"name": "Prompt-cache prefix guardian", "provider": "TextForAgents LLC", "support": "support@textforagents.com", "slug": "prompt-cache-prefix-guardian", "what": "Cache-bust forensics and TTL-fit verdicts for metered agent loops. The guardian fingerprints the cacheable prefix per breakpoint (tools -> system -> messages) in two forms \u2014 semantic and representation \u2014 so it names the busting field class exactly (tool rename vs reorder vs definition change vs tool-list churn by owning MCP server; dynamic values like timestamps and UUIDs; pure serialization-order changes separated from content changes), answers pre-flight whether the next turn will hit, and prices the loop's measured cadence against every purchasable TTL \u2014 FIT / INVERSION / SUBOPTIMAL, signed. Attribution is identical across direct API, Bedrock, and OpenRouter usage surfaces.", "limits": "LIMITATION, stated plainly: the lab figures (17.3% miss share over 150 archetype turns; 3 of 8 archetypes in TTL INVERSION) are archetype measurements over 8 house-shaped synthetic loops, NOT live-loop telemetry. The one-week live-loop dogfood report (packet blueprint item 7) does not exist yet; until it does, no figure on this surface is live telemetry. Dialect adapters (direct API / Bedrock / OpenRouter) normalize the documented provider usage field names. Re-proving cadence: the adapters are re-verified against the providers' current documented usage surfaces weekly (see DIALECTS.md in the product directory; results recorded there and in monitoring). An unknown dialect is rejected, never silently accepted.", "prices": {"session_audit_usd": 0.05, "sidecar_per_turn_usd": 0.002, "fleet_usd_per_month": 15, "fleet_includes": "hit-rate ledger + step-change alerts ONLY; per-turn forensics never ride the flat tier"}, "trial": "First session audit free, one time per operator account, enforced per account AND per payer wallet; a second account for the same operator does not re-grant. Sidecar turns and Fleet months are paid from the first turn/month. There is no perpetual free tier.", "how_to_start": "POST /register {account_name, payer_wallet} -> per-customer token (shown once, SHA-256 at rest). POST /audit (Bearer) with {turns:[{prev,curr,usage?,dialect?}], intervals?, chosen_ttl?, tokens?, session_id?} for a session audit with an Ed25519-signed receipt \u2014 the first is the one-time trial, later audits are x402 at $0.05 (X-PAYMENT header). POST /turn (Bearer <redacted> X-PAYMENT $0.002) for one metered sidecar turn. POST /preflight and POST /ttl-fit (Bearer) for the pre-flight hit/miss answer and the TTL verdict. POST /subscribe (Bearer <redacted> X-PAYMENT $15) for the Fleet ledger tier; GET /ledger (Bearer, Fleet) for your hit-rate ledger and step-change alerts. The same operations are MCP tools at POST /mcp. Verify any receipt at POST /receipts/verify.", "pay_to": "0x7a482F3B58780519880a6A13F983E958f2Ed6A61", "network": "base (eip155:8453)", "asset": "USDC", "signing_keys": "/.well-known/signing-keys"}