x402 Micropayments MCP

Measured conclusion: Deep-tested. L2 outcome: tools_ok.

Pay-per-call US city property compliance and Base tx checks, paid in USDC on Base via x402.

Add to your agent

Copy this into your MCP client config:

{
  "mcpServers": {
    "x402 Micropayments MCP": {
      "url": "https://x402-mcp.onrender.com/mcp/mcp",
      "transport": "streamable-http"
    }
  }
}

Measured tools (20)

• x402.agent_card read-only

  Return the A2A Protocol v1.0 Agent ID Card and MCP server card. Optional target_id filters to a skill id, name, or tag.

  Parameters:

  • agent_id — string — Optional calling agent identifier for quota tracking.
  • target_id — string — Optional skill ID, tool name, or tag to inspect. Omit for the full server agent card.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• x402.discover read-only

  Discover paid HTTP APIs in the x402 Bazaar via the facilitator catalog. Call this first to find a resource URL, then x402.probe and x402.pay_and_fetch.

  Parameters:

  • limit — integer — Maximum number of catalog entries to return. Default 20. Range 1–100.
  • query — string — Optional Bazaar search substring. Example: 'weather' or 'image'. Omit to list recent paid HTTP services.
  • agent_id — string — Optional agent identity for quota accounting. Example: 'agent-42'. Omit to use the anonymous free-tier id.
  • max_price_usdc — number — Optional USDC price ceiling. Example: 0.05. Omit to include any listed price.

  Hints: read-only yes · destructive no · idempotent yes · open-world yes

• x402.probe read-only

  Probe a URL for HTTP 402 PAYMENT-REQUIRED terms using the x402 client SDK. Use before x402.pay_and_fetch to inspect price, network, and payTo without spending.

  Parameters:

  • url (required) — string — Absolute HTTP URL to probe. Example: 'https://x402-mcp.onrender.com/us/mn/property-check?address=1700%20Penn%20Ave%20N'.
  • method — string — HTTP method for the probe. Default GET. Example: 'GET' or 'POST'.
  • headers — object — Optional extra request headers as a string map. Example: {"Accept": "application/json"}. Omit if none.
  • agent_id — string — Optional agent identity for quota accounting. Omit for the anonymous free-tier id.

  Hints: read-only yes · destructive no · idempotent yes · open-world yes

• x402.pay_and_fetch

  Pay USDC via x402 and fetch a protected HTTP resource in one call. Requires EVM_PRIVATE_KEY on this host; otherwise use x402.probe for a no-spend 402.

  Parameters:

  • url (required) — string — Absolute paid HTTP URL to fetch after settling USDC.
  • body — string — Optional raw request body for POST/PUT. Omit for GET.
  • method — string — HTTP method for the paid request. Default GET.
  • headers — object — Optional extra request headers as a string map. Omit if none.
  • agent_id — string — Optional agent identity for quota accounting.
  • max_price_usdc — number — Optional spend ceiling in USDC. Example: 0.10. Calls above this are blocked.
  • preferred_network — string — Preferred CAIP-2 network. Example: 'eip155:8453' (Base mainnet). Omit to use the server default. Call x402.networks to list options.

  Hints: read-only no · destructive no · idempotent no · open-world yes

• x402.build_seller

  Build seller-side x402 payment requirements for your own HTTP resource. Pass resource_url plus discovery_* fields to catalog the endpoint in Bazaar.

  Parameters:

  • price — string — List price string. Default '$0.01'. Example: '$0.05'.
  • pay_to — string — 0x recipient for USDC. Example: '0x67ff…'. Omit to use X402_PAY_TO_ADDRESS.
  • scheme — string — x402 payment scheme. Default 'exact'.
  • network — string — CAIP-2 settlement network. Default eip155:84532 (Base Sepolia). Mainnet: eip155:8453.
  • agent_id — string — Optional agent identity for quota accounting.
  • mime_type — string — Resource MIME type. Default application/json.
  • description — string — Human-readable description embedded in PAYMENT-REQUIRED.
  • discoverable — boolean — If true, embed the Bazaar discovery extension. Omit to use server default.
  • resource_url — string — Public URL of the paid resource. When set with discovery_* fields, Bazaar catalogs the endpoint after a settled payment.
  • discovery_method — string — HTTP method advertised to Bazaar. Default GET.
  • discovery_input_example — object — Optional example input object for Bazaar. Omit if none.
  • discovery_output_example — object — Optional example output object for Bazaar. Omit if none.

  Hints: read-only no · destructive no · idempotent yes · open-world yes

• x402.verify

  Verify an x402 PAYMENT-SIGNATURE against PAYMENT-REQUIRED terms via the facilitator. Call after a buyer presents a signature and before releasing paid content.

  Parameters:

  • payment_signature (required) — string — PAYMENT-SIGNATURE header value from the buyer.
  • payment_required (required) — string — PAYMENT-REQUIRED JSON/header the signature is meant to satisfy.
  • agent_id — string — Optional agent identity for quota accounting.

  Hints: read-only no · destructive no · idempotent no · open-world yes

• x402.networks read-only

  List supported settlement networks, facilitators, and x402 v2 header names. Call when choosing a preferred_network for x402.pay_and_fetch or x402.build_seller.

  Parameters:

  • agent_id — string — Optional agent identity for quota accounting.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• commerce.pro_requirements read-only

  Build x402 payment requirements to purchase the Pro quota tier. Next: pay those terms, then commerce.activate_pro with the signature.

  Parameters:

  • agent_id — string — Optional agent identity the Pro grant will attach to.

  Hints: read-only yes · destructive no · idempotent yes · open-world yes

• commerce.activate_pro

  Verify a Pro-tier x402 payment and unlock Pro quota limits for the agent. MCP-native: call without payment to receive x402 requirements in the tool result, then retry with _meta['x402/payment'] (@x402/mcp client). Legacy: pass PAYMENT-SIGNATURE + PAYMENT-REQUIRED after commerce.pro_requirements.

  Parameters:

  • agent_id — string — Agent identity to grant Pro quota. Must match the requirements call.
  • payment_required — string — Legacy PAYMENT-REQUIRED from commerce.pro_requirements. Ignored when using MCP _meta payment.
  • payment_signature — string — Legacy HTTP-style PAYMENT-SIGNATURE. Omit for MCP x402/payment transport.

  Hints: read-only no · destructive no · idempotent no · open-world yes

• commerce.credits_requirements read-only

  Build x402 payment requirements to buy a pack of per-use MCP tool credits. Next: pay those terms, then commerce.purchase_credits with the signature.

  Parameters:

  • credits — integer — Credit pack size to buy. Example: 100. Omit to use the server default pack.
  • agent_id — string — Optional agent identity the credits will attach to.

  Hints: read-only yes · destructive no · idempotent yes · open-world yes

• commerce.purchase_credits

  Verify an x402 payment and add per-use tool credits to the agent. MCP-native: call without payment for x402 requirements, then retry with _meta['x402/payment']. Legacy: PAYMENT-SIGNATURE + PAYMENT-REQUIRED after commerce.credits_requirements.

  Parameters:

  • credits — integer — Credit pack size that was purchased. Must match the requirements call.
  • agent_id — string — Agent identity to credit.
  • payment_required — string — Legacy PAYMENT-REQUIRED from commerce.credits_requirements.
  • payment_signature — string — Legacy PAYMENT-SIGNATURE. Omit for MCP x402/payment transport.

  Hints: read-only no · destructive no · idempotent no · open-world yes

• swarm.research

  Run the swarm agency: compose a research product from free inputs and list it for resale. Pass allow_paid_inputs=true only when buying upstream x402 services is intended.

  Parameters:

  • topic (required) — string — Research topic to compose. Example: 'Base mainnet gas window'.
  • agent_id — string — Seller agent identity that will own the listing.
  • max_price_usdc — number — Optional USDC ceiling for any paid upstream inputs.
  • allow_paid_inputs — boolean — If true, buy upstream x402 services before composing. Default false (free inputs only, unsold inventory costs nothing).

  Hints: read-only no · destructive no · idempotent no · open-world yes

• swarm.settle

  Verify and settle a buyer's x402 payment for a listed composite product and record revenue. Call with product_id plus PAYMENT-SIGNATURE after the buyer pays.

  Parameters:

  • product_id (required) — string — Listed composite product id. Example: the hex id from swarm.research.
  • payment_signature (required) — string — PAYMENT-SIGNATURE from the buyer.
  • payment_required (required) — string — PAYMENT-REQUIRED terms for this product.
  • agent_id — string — Seller agent identity recording the sale.

  Hints: read-only no · destructive no · idempotent no · open-world yes

• swarm.revenue read-only

  Get swarm composite economics: spend, composite sales, LTV:CAC, margins, per-source scores. total_revenue_usdc is swarm listings only; storefront.revenue_usdc is the full settled ledger. Call after swarm.research or swarm.settle to inspect realized economics.

  Parameters:

  • agent_id — string — Optional agent identity for quota accounting.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• pulse.base read-only

  Get live Base Network Pulse: base fee, EIP-1559 projection, utilization, USD settlement cost, verdict. Call before settling on Base when you need a settle-now vs hold recommendation.

  Parameters:

  • depth — integer — Blocks to sample. Example: 12. Omit to use the server default.
  • agent_id — string — Optional agent identity for quota accounting.

  Hints: read-only yes · destructive no · idempotent yes · open-world yes

• ops.metrics read-only

  Get host OS telemetry: CPU, memory, swap, disk, network, and an ok/warn/critical health verdict. Call to diagnose this MCP host; set include_processes=true for top memory processes.

  Parameters:

  • agent_id — string — Optional agent identity for quota accounting.
  • include_processes — boolean — If true, include top processes by memory. Default false.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• city.list read-only

  List US City Open-Data Compliance Network cities with paid_url, sample_url, and price. Call first, then city.sample, then city.check for the paid address lookup.

  Parameters:

  • agent_id — string — Optional agent identity for quota accounting.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• city.sample read-only

  Get a free fixed-address property compliance sample for one US city code. Use before city.check to validate city_code and response shape without paying.

  Parameters:

  • city_code (required) — string — City code from city.list. Examples: 'mn', 'sea', 'nyc', 'chi'.
  • agent_id — string — Optional agent identity for quota accounting.

  Hints: read-only yes · destructive no · idempotent yes · open-world yes

• city.check

  Paid US city property compliance check (MCP seller x402). Unpaid calls return PaymentRequired with accepts; pay via _meta['x402/payment']. Prefer city.sample first. Price: $0.01 per call (x402, USDC on Base/Solana/Arbitrum).

  Parameters:

  • city_code (required) — string — City code from city.list. Example: 'mn'.
  • address (required) — string — Street address to check. Example: '1700 Penn Ave N' or '1 Centre St'.
  • agent_id — string — Optional agent identity for quota accounting.
  • max_price_usdc — number — Optional USDC spend ceiling. Example: 0.05.
  • preferred_network — string — Preferred CAIP-2 network. Example: 'eip155:8453'.

  Hints: read-only no · destructive no · idempotent no · open-world yes

• a2a.resolve_card read-only

  Discover and inspect an external Agent-to-Agent (A2A) node by domain or URL. Fetches .well-known/agent-card.json, validates protocol compatibility, checks for a2a-x402 and AP2 payment extensions, and extracts callable skills with pricing.

  Parameters:

  • target (required) — string — Host domain or full URL of the agent (e.g. 'agent.example.com' or 'https://agent.example.com/.well-known/agent-card.json')
  • agent_id — string — Optional calling agent identifier for quota tracking.

  Hints: read-only yes · destructive no · idempotent yes · open-world yes

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