# naxytra

> Pay-per-call tools for AI agents. Discovery is free and every caller gets 20 free tool calls per UTC day, no key or wallet needed. After that each call costs $0.01 USDC on Base mainnet ($0.001 USDC on Base Sepolia testnet), or $0.02 for the two attesting tools, paid with x402 v2 (gasless EIP-3009 USDC authorization) and settled through the Coinbase CDP facilitator only after the call succeeds, or 3 credits with a prepaid spend key (6 credits for the two attesting tools). No account needed.

naxytra is the umbrella for two services: the xytara runtime (pay, route, execute, settle) and the xoonya proof engine (post-quantum proof verification). Each paid call returns a signed delivery receipt (Ed25519 + ML-DSA-65).

## Free allowance

- 20 free tool calls per UTC day, no key or wallet needed, on the MCP server https://mcp.naxytra.com/mcp. Just connect; no key, no wallet, no account.
- Each MCP tool result reports the remaining free calls in _meta["naxytra.com/allowance"].
- After the allowance, a tools/call costs $0.01 USDC via x402 or 3 credits with a spend key ($0.02 or 6 credits for the two attesting tools, x402.verify-receipt and tx.status).

## Spend key (prepaid credits)

- Buy: https://www.naxytra.com/buy (in-browser wallet flow or a Node snippet): $1.00 USDC on Base mainnet = 400 credits (1 credit = $0.0025; an MCP call costs 3 credits, so about 133 calls per top-up)
- Format: xytara_spend_<hex>; shown once; keep it secret
- Send it to the MCP server as Authorization: Bearer xytara_spend_... (preferred), or X-Naxytra-Key: <key>, or ?key=<key> appended to https://mcp.naxytra.com/mcp for clients that cannot set headers
- Client config snippets (Claude Desktop, Claude Code, Cursor, VS Code, Windsurf, LangChain, OpenAI Agents SDK, x402-native): https://www.naxytra.com/setup
- Balance: GET https://api.naxytra.com/v1/credits/balance with the same Authorization header -> {account_id, available_units}
- Card checkout is coming.

## Buy

- MCP server (Streamable HTTP): https://mcp.naxytra.com/mcp
  - 17 deterministic tools: summarize, zones.lookup, catalog, reply.draft, json.validate, text.extract, html.to-text, text.chunk, x402.decode, keccak256, address.validate, x402.verify-receipt, tx.status, abi.encode, abi.decode, merkle.verify, eip712.hash
  - Free: initialize, tools/list, resources, prompts, the catalog tool, and the daily allowance above
  - Paid: every other tools/call past the allowance, $0.01 USDC per call (Base mainnet) · $0.001 (Base Sepolia), or 3 credits with a spend key; the two attesting tools (x402.verify-receipt, tx.status) cost $0.02 ($0.002 on Base Sepolia) or 6 credits
  - An unpaid tools/call without a key returns a payment-required tool result (x402 MCP transport); attach the signed payment and retry
  - HTTP-402 variant for fetch-wrapper x402 clients: https://mcp.naxytra.com/mcp/http402
- Runtime execute: POST https://api.naxytra.com/x402/commands/execute (also https://api.naxytra.com/x402/mcp/tools/invoke), same price
  - task_ref adapter.mcp.invoke: any of the 17 MCP tools
  - task_ref adapter.xoonya.invoke: post-quantum proof verification (proof.verify-signature, proof.verify-bundle)
  - other catalog task_refs are reference entries and return 501 capability_not_executable (no charge)
- A2A: message/send on https://api.naxytra.com/v1/a2a with metadata.task_ref set to one of the two tasks above, same price
- Credits: POST https://api.naxytra.com/x402/credits/topup, $1.00 USDC on Base mainnet buys 400 credits (1 credit = $0.0025; a task costs 1-8 credits, an MCP call 3). The response returns the spend key (Bearer xytara_spend_...); use it on the MCP server as above, or on the runtime with payment_preference "credits_first". Human page: https://www.naxytra.com/buy.

## Verified answers (signed attestations)

- Tools: x402.verify-receipt, tx.status on https://mcp.naxytra.com/mcp. Next to the normal result they return a signed attestation in result._meta["naxytra.com/attestation"] stating the on-chain fact the tool verified: x402.verify-receipt attests settlement matched / not matched; tx.status attests the transaction status, block and confirmations.
- Format: naxytra-attestation/1; JCS (RFC 8785) canonical JSON; signed with Ed25519 + ML-DSA-65 (same keys as the delivery receipts: https://mcp.naxytra.com/.well-known/delivery-receipt-keys); carries evidence_sha256 (SHA-256 of the evidence the attestation was made over) and bindings (external bindings inside the signed bytes (ctp/1: a chronology-protocol binding tag, when the issuer is anchoring))
- Anchoring: Attestations issued with a ctp/1 binding are anchored in chronology-protocol epochs (an open proof-of-work timestamping protocol by machine-native). The first two naxytra attestations are in epoch 10: vector naxytra-binding-bundle.cbor, bundle sha256 dc14bc557abc666288950220ff2117012dd9a90106434a404735f012010947a5, verifiable by anyone with chronology-protocol's verify_sandwich.py (SANDWICH_PASS). Current state: anchored in the laboratory chain (block 1365) and timestamped into public Bitcoin via OpenTimestamps, attested in Bitcoin blocks 972765–972808. The first delegation-log checkpoint (att_61682b456a1d) is in epoch 11: vector naxytra-delegation-binding-bundle.cbor, bundle sha256 339e89255abf7b3763d3ff112db671c6f983dff6c799471e8a262a373bdc938b, anchored in the laboratory chain (block 1368) and timestamped into public Bitcoin via OpenTimestamps, attested in Bitcoin blocks 972955–973014. Later weekly checkpoints are archived as issued and anchored in the next monthly epoch.
- Price: $0.02 per call via x402 (20000 units on Base mainnet; 2000 on Base Sepolia) or 6 credits with a spend key. Still covered by the 20-call free daily allowance. All other tools stay $0.01 / 3 credits.
- Free: GET https://mcp.naxytra.com/attestations/<id>, POST https://mcp.naxytra.com/attestations/verify, and offline verification with the xytara npm client (verifyAttestation)

## Teams (beta)

- The owner key is the key a top-up returns (xytara_spend_...). It is the Bearer for every team route. An agent key is used in a client exactly like a spend key (see https://www.naxytra.com/setup); human page: https://www.naxytra.com/teams
- POST https://api.naxytra.com/v1/credits/agents: Mint a capped agent key (shown once)
- GET https://api.naxytra.com/v1/credits/agents: List agent keys (never the tokens)
- POST https://api.naxytra.com/v1/credits/agents/:id/revoke: Revoke an agent key
- GET https://api.naxytra.com/v1/credits/activity: Audit trail: which agent spent what on which tool, when
- GET https://api.naxytra.com/v1/credits/agents/log: Delegation log: every mint and revoke of this account's agent keys (full events)
- GET https://api.naxytra.com/v1/credits/agents/:id/proof: Delegation proof for one agent key: its events, the hash chain to the head, the signed checkpoint
- Mint body: {label, max_units_per_call, max_units_per_day, max_units_total, expires_at_iso, allowed_tools, agent_public_key (optional)}. With agent_public_key the key is key-bound: every spend needs a fresh request-bound ed25519 signature. Caps are enforced on every spend; an agent key cannot mint keys or see other agents.
- Key-bound spend: the agent signs naxytra-spend-auth:<credential_id>:<timestamp>:<sha256 of the binding JSON> where the JSON is ["naxytra-spend-binding/v1", <account>, "3" | "6", "adapter.mcp.invoke"]
- Delegation log: every agent-key mint and revoke is an append-only, hash-chained event; public head/feed/checkpoint at /v1/delegation-log/*; owners fetch a delegation proof per key at GET /v1/credits/agents/:id/proof; checkpoints are signed attestations that can carry a chronology binding. The checkpoint is a naxytra-attestation/1 over the log head, signed with the delivery-receipt keys; while an anchoring session is open it carries a ctp/1 chronology binding inside the signed bytes, so an anchor outside the runtime bounds the head in time.
- Delegation log format naxytra-delegation-log/1, public (no key): https://api.naxytra.com/v1/delegation-log/head · https://api.naxytra.com/v1/delegation-log/feed · https://api.naxytra.com/v1/delegation-log/checkpoint
- Included with credits for now: no extra charge. Business plans later.

## Payment terms

- Base mainnet (eip155:8453): USDC 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, $0.01 per call (amount 10000, 6 decimals); attesting tools $0.02 (amount 20000)
- Base Sepolia (testnet) (eip155:84532): USDC 0x036CbD53842c5426634e7929541eC2318f3dCF7e, $0.001 per call (amount 1000, 6 decimals); attesting tools $0.002 (amount 2000)
- payTo: 0x7cd2E0Ed2721319B20FAac4109774d030833F84D (the payment-required challenge from the endpoint is authoritative)
- Scheme: x402 v2 exact; facilitator: Coinbase CDP; settlement only after a successful call
- Delivery receipt keys: https://mcp.naxytra.com/.well-known/delivery-receipt-keys, https://api.naxytra.com/.well-known/delivery-receipt-keys
- Runtime responses carry an X-Request-Id header (errors include request_id); quote it when asking for support

## Sell (open provider network)

- Register: POST https://api.naxytra.com/v1/provider-network/register (contract: https://api.naxytra.com/v1/provider-network/contract; human page: https://www.naxytra.com/providers)
- Open registration (no API key): POST your public HTTPS /execute endpoint, the capabilities you serve, your revenue_share_bps and your payout_address; you get an owner_secret back. Provider endpoints must be public HTTPS; private, loopback and link-local addresses are refused.
- An operator reviews and activates (activation requires a payout_address on your record); paid x402 calls are routed to active providers only — the most specific capability match first, then by reputation, with failover. Settlement only on your success; a failed call is not charged and earns nothing.
- A 2xx that carries result.output, output_payload or output is a delivery; a 2xx without one is not charged, earns nothing and is not retried elsewhere.
- You set your own price per capability with offers ({ tool_name | task_ref, title, price_usd }, $0.001–$100.00 in $0.001 steps): a credits call is debited its credits equivalent (a $0.001 call costs 1 credit), a buyer's x402 challenge advertises your price in USDC (one x402 payment is at least $0.005, which covers the per-payment settlement fee), and your revenue share is always computed on your own price. Provider tools are paid on Base mainnet only (never with testnet USDC). Every active provider's offers are listed under provider_offers in the runtime catalog (GET https://api.naxytra.com/v1/catalog).
- An offer with a tool_name is also listed by the naxytra MCP server (tools/list, after the built-in tools) and a tools/call for it is proxied to the runtime at your price — MCP clients discover and pay for your tool with no integration on your side.
- Revenue share up to 80%, accrued exactly in USDC base units ($0.000001), so even a $0.001 price earns its full share; paid out on-chain in USDC on Base by a weekly payout sweep once your available balance reaches $1.00; read your earnings with your owner_secret.
- Weekly payout sweep (Mondays, UTC): every active provider with at least $1.00 available is paid in full to its payout_address; the operator can also pay out any time. Idempotent, double-pay-safe, public on Basescan. Rotate your owner_secret any time with POST /v1/provider-network/providers/<provider_id>/rotate-secret (authenticate with the current secret; the new one is shown once).
- Three providers are active today: two first-party and one independent founding provider. More founding providers wanted. Contact: naxytra@gmail.com
- Directory: https://api.naxytra.com/v1/provider-network/providers

## Buyer console

- Buyer console (browser): paste a spend key at https://www.naxytra.com/console to see the account's balance, every credit spend and its agent keys, and to mint or revoke agent keys. The key stays in the page; the page talks only to the runtime.

## Not live

- USD₮ / Celo settlement is not live.
- L402 (Lightning) is a verification rail only; it is not live-settled.
- Card checkout is coming; today, buy with x402 or the x402 credits top-up.
- Base Sepolia (testnet) credit top-ups are not enabled; use the free daily allowance to try things.
- Other chains and rail families listed in the catalog (for example Hedera, Kaspa, Polkadot, DigiByte, Constellation, Solana, Antelope, BSV) are catalog/reference entries, not live settlement.
- XNYA proof verification is machine-evidence verification, not an identity, custody or chain-truth claim.

## Links

- [Agents and pricing](https://www.naxytra.com/agents)
- [Buy credits / get a spend key](https://www.naxytra.com/buy)
- [Set up your MCP client](https://www.naxytra.com/setup)
- [Teams (beta)](https://www.naxytra.com/teams)
- [Buyer console](https://www.naxytra.com/console)
- [Become a provider](https://www.naxytra.com/providers)
- [Quickstart](https://www.naxytra.com/quickstart)
- [x402 manifest](https://www.naxytra.com/.well-known/x402)
- [A2A agent card](https://www.naxytra.com/.well-known/agent-card.json)
- [MCP server card](https://www.naxytra.com/.well-known/mcp/server-card.json)
- [Agent discovery index](https://www.naxytra.com/v1/agent-discovery-index)
- [On-chain proof](https://www.naxytra.com/proof)
- [Support](https://www.naxytra.com/support)
- [Terms of service](https://www.naxytra.com/terms) · [Acceptable use](https://www.naxytra.com/acceptable-use) · [Privacy](https://www.naxytra.com/privacy) · [Refunds](https://www.naxytra.com/refunds)

## Reference (catalog, not all live)

- [Catalog](https://www.naxytra.com/catalog): the broad catalog of protocol, framework, rail and lane families. Entries there are reference material unless listed under Buy above.
- [Proof verification services](https://xoonya.onrender.com/v1/proof-center/verification-services/summary)