How do I install TensorFeed X402 Base Reader?

Copy the stdio config for Cursor, Claude Desktop, Claude Code, or VS Code on this page. It uses the publisher's install, not a PlugMCP proxy.

Does TensorFeed X402 Base Reader need an API key?

The publisher lists these environment variables: TENSORFEED_RPC_URL.

What transport does TensorFeed X402 Base Reader use?

TensorFeed X402 Base Reader runs locally over stdio.

When was TensorFeed X402 Base Reader last checked?

Last checked 2026-11-07. Read-only Base mainnet reader. Verifies x402 payment settlements + AFTA federation status.

TensorFeed X402 Base Reader MCP server

Power your agent

Add this server

The publisher's own command. Not a PlugMCP endpoint.

Add to Cursor Add to VS Code Run on PlugMCP

Host a copy with our keys and logs.

Local command

npx -y @tensorfeed/[email protected]

Credentials from the publisher

TENSORFEED_RPC_URL — Optional Base mainnet RPC endpoint (Alchemy, Infura, etc) for higher rate limits. Must match the allowlist in src/rpc/allowlist.ts; non-allowlisted URLs fall back to public Base RPC with a stderr warning. Defaults to https://mainnet.base.org if unset.

Claude Code has no install link for a local command. Copy the command below and run it in a terminal.

shClaude Code

1TENSORFEED_RPC_URL=<secret> claude mcp add ai.tensorfeed-x402-base-mcp -- npx -y @tensorfeed/x402-base-mcp@0.2.1

Run in a terminal.

jsonClaude Desktop

1{2  "mcpServers": {3    "ai.tensorfeed-x402-base-mcp": {4      "command": "npx",5      "args": [6        "-y",7        "@tensorfeed/[email protected]"8      ],9      "env": {10        "TENSORFEED_RPC_URL": "<secret>"11      }12    }13  }14}

claude_desktop_config.json

Local · npmPublisher installStep-by-step: add this in Claude

Remote URL or a command on your machine? How the two installs differ

Run on PlugMCP

Host a copy with our keys and logs.

A new server you create. It is not this listing's official endpoint. Use the publisher install when you want their URL and their credentials.

Launch

Server facts

Local

Transport: stdio
Version: 0.2.1

Tools

No tool list yet. Remote servers get one after the first health check.

FAQ

Questions

@tensorfeed/x402-base-mcp

Read-only MCP server for verifying x402 USDC settlements on Base mainnet. Drop it into any MCP-compatible agent (Claude Desktop, Claude Code, Cursor, ChatGPT) to independently audit x402 payment receipts on-chain, parse publisher .well-known/x402 manifests, and check AFTA federation status. No private keys, no signing, no broadcasts.

npm install -g @tensorfeed/x402-base-mcp

Relationship to Coinbase Base MCP

Coinbase shipped Base MCP (the official mcp.base.org server, launched May 2026) as the transact-side MCP: it connects an agent to a Base Account and lets the agent propose swaps, transfers, and x402 payments that the user approves in-wallet.

This package, @tensorfeed/x402-base-mcp, is the verify-side MCP. Once an x402 payment has been made (by Base MCP, by a server-side @coinbase/x402 middleware, or by any other x402 client), this server lets the calling agent independently check the on-chain settlement, parse the publisher's /.well-known/x402 manifest, and audit the receipt. Read-only chain visibility, no wallet.

The two are complementary, not competing. Use Base MCP to pay. Use this MCP to verify.

Why a separate verify MCP

x402 is a payment protocol where agents pay merchants in USDC on Base for paid API responses. When an agent receives a payment receipt back, it has two options for confirming that the settlement actually happened the way the receipt claims:

Trust the merchant
Read the on-chain Transfer event itself

Most existing EVM MCP servers either require a private key (so the agent can also send transactions, which is operationally risky and unnecessary for verification), or are generic multi-chain readers that don't speak x402. This server is the read-only, x402-aware option. Drop it into a Claude Desktop or Claude Code session and any agent can verify x402 payments without operating a wallet.

The TensorFeed-flavor tools (verify_afta_federation, tf_payment_lookup) compose the same primitives against TF's canonical surfaces and demonstrate the pattern. Use them or ignore them; the generic tools work fine on their own.

Installation

Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "tensorfeed-x402-base": {
      "command": "npx",
      "args": ["-y", "@tensorfeed/x402-base-mcp"]
    }
  }
}

Claude Code

claude mcp add tensorfeed-x402-base -- npx -y @tensorfeed/x402-base-mcp

Optional: bring your own RPC

The server defaults to the public Base RPC (https://mainnet.base.org), which is fine for casual use. For heavier workloads, set an Alchemy or Infura URL via TENSORFEED_RPC_URL. The URL must match the allowlist in src/rpc/allowlist.ts; anything else falls back to the public endpoint and logs a warning to stderr.

export TENSORFEED_RPC_URL="https://base-mainnet.g.alchemy.com/v2/YOUR_KEY"

Affiliate links if you don't already have an account:

Alchemy: https://www.alchemy.com/
Infura: https://www.infura.io/

Tools

Generic Base reads

Tool	Description
`balance`	Native ETH balance for an address
`usdc_balance`	USDC (Circle native bridged) balance for an address
`block_number`	Latest Base block number
`get_tx_receipt`	Full tx receipt with status, gas, and logs summary
`call`	Read-only contract call (eth_call, never broadcasts)
`recent_transfers`	USDC Transfer events involving an address over N blocks

x402-native verification

Tool	Description
`verify_x402_settlement`	Given a tx hash, expected recipient, and expected USDC amount, returns a structured verdict on whether the on-chain Transfer event matches.
`parse_x402_manifest`	Fetches `https://{domain}/.well-known/x402.json`, returns the structured manifest.
`usdc_recent_payments_to`	USDC transfers TO an address over N blocks; the merchant-side view.
`probe_x402_endpoint`	Probes any https URL and reports whether it returns a canonical x402-paid 402 response with `accepts[]`.
`decode_x402_payment_payload`	Offline decode of a base64 `X-PAYMENT` header (Coinbase x402 V2): returns scheme, network, version, EIP-3009 authorization, signature.

TensorFeed flavor

Tool	Description
`verify_afta_federation`	Calls TensorFeed's AFTA certification endpoint for a domain, returns a scored checklist.
`tf_payment_lookup`	Checks whether a tx hash is a USDC payment to TensorFeed's canonical wallet on Base.
`x402_publisher_health`	Returns current outcome + 24h/7d uptime + recent series for a domain monitored by TensorFeed's hourly x402 status probe.
`afta_federation_members`	Returns the canonical curated list of confirmed AFTA federation members (TF origin + federated members).

Examples

Verify an x402 settlement (works on TensorFeed's first canonical V2 payment):

verify_x402_settlement({
  tx_hash: "0xe20c57d8aa6df63f75ce7a4e4c0cab492eb7fa672a23cd8fd59967eb6b66bd67",
  expected_recipient: "0x549c82e6bFC54bdaE9A2073744CBC2AF5D1FC6D1",
  expected_amount_usdc: "0.02"
})
// returns { ok: true, verified: true, matches: [...] }

Inspect a publisher's x402 manifest:

parse_x402_manifest({ domain: "tensorfeed.ai" })

Check AFTA certification:

verify_afta_federation({ domain: "tensorfeed.ai" })

Threat model

Read-only chain-visibility MCP. The full picture is in SECURITY.md; the short version:

No private keys, no signing, no broadcasts. The server cannot move funds.
Input validators on every tool reject malformed inputs (bad checksums, malformed hashes, URL-shaped domains, private/loopback hostnames).
Output sanitization strips C0/C1 control characters and zero-width / direction-override marks from every string returned to the calling agent.
External strings carry an _origin: "external" marker so the calling agent knows the value came from a third party.
50 KB response cap on serialized tool output; oversized responses collapse to a structured stub.
RPC allowlist limits self-hosters to known endpoints; arbitrary URLs are rejected and fall back to public Base RPC.
No telemetry, no phone-home, no analytics.
Provenance: npm releases are published via GitHub Actions OIDC with cryptographic provenance attestations. Verify with npm audit signatures.

Report security issues to [email protected]. Please do not file a public issue or CVE for an unfixed vulnerability.

License

MIT

Coinbase Base MCP - the official transact-side MCP for Base. Pair with this package for a full pay + verify loop: Base MCP signs the x402 payment, this package independently confirms the settlement on-chain.
@tensorfeed/mcp-server - companion package, the TensorFeed data MCP (news, status, models, benchmarks, premium endpoints). Complementary role: this server verifies x402 payments on-chain; mcp-server wraps the TF data API as MCP tools.
TensorFeed - AI ecosystem data layer
TensorFeed developers - free + premium API for AI agents
Agent Fair-Trade Agreement (AFTA) - open standard for honest agent commerce
x402 spec - the payment protocol this MCP verifies

TensorFeed X402 Base Reader

Add this server

Host a copy with our keys and logs.

Server facts

Tools

Questions

How do I install TensorFeed X402 Base Reader?

Does TensorFeed X402 Base Reader need an API key?

What transport does TensorFeed X402 Base Reader use?

When was TensorFeed X402 Base Reader last checked?

Documentation

@tensorfeed/x402-base-mcp

Relationship to Coinbase Base MCP

Why a separate verify MCP

Installation

Claude Desktop

Claude Code

Optional: bring your own RPC

Tools

Generic Base reads

x402-native verification

TensorFeed flavor

Examples

Threat model

License

Related