x402 · USDC on Base

One endpoint. No account. Pay per call.

GTXAgent sells live crypto data to other agents over x402. The 402 challenge carries the price, the asset and the address; your agent pays in USDC on Base and gets JSON back. The seven public x402 routes need no signup or API key. The hosted MCP endpoint uses a prepaid tenant key; the local stdio bridge pays from your own wallet.

Open the machine manifest

Resources

What you can buy

$0.01 · GET

Market pulse

One live Base snapshot: every allowed registry token quoted in USDC, with unavailable legs named instead of hidden.

/x402/market/pulse

$0.005 · GET

Token registry

The allowed Base token registry: symbol, address and decimals. No quote-provider calls.

/x402/market/tokens

$0.01 · GET

Token decision

One deterministic yes / no / abstain decision with reasons, confidence, invalidation and sources. Closed 1h candles; no model guess.

/x402/decision?token=WETH

Aggregate tools

One call, one upstream paid for you

Fixed-price pass-through tools. The price is in the 402 challenge; the upstream provider and its cost are never selected by the caller.

/x402/aggregate/token-safety — $0.03 — token safety, ownership powers and holder concentration.
/x402/aggregate/x-search — $0.015 — recent X/Twitter posts by words, author and likes.
/x402/aggregate/token-price — $0.04 — live token price and market data.
/x402/aggregate/market-open — $0.015 — whether a named exchange is open at an instant.
/x402/aggregate/agent-recommend — $0.02 — which x402 API fits a task.
/x402/aggregate/trending-coins — $0.04 — trending coins with rank and price.
/x402/aggregate/whale-coverage — $0.02 — coverage summary for the whale-flow dataset.

MCP bridge

Use the tools from an MCP client

The hosted Streamable HTTP endpoint exposes the same seven tools at https://app.gtxagent.com/mcp. Authenticate with Authorization: Bearer gtx_mcp_…; calls are charged to your prepaid credits and the upstream is paid by GTXAgent, so your agent needs no wallet. A per-key daily cap ($5 by default) limits exposure. Keys are issued per tenant — request one.

curl -X POST https://app.gtxagent.com/mcp \
  -H "Authorization: Bearer $GTX_MCP_KEY" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

The local stdio bridge remains the zero-account path: it pays the public x402 route from your own Base wallet, so GTXAgent never holds your key. Run GTX_X402_BUYER_KEY=0x… npm run --silent mcp, or point your MCP client at node --experimental-strip-types scripts/mcp-server.ts. Use a dedicated wallet with a small USDC balance. The npm package is live; use the hosted key path below.

npm package: run GTX_MCP_KEY=… npx -y gtxagent-mcp, or put it in your MCP host config. It is the same hosted proxy and needs no wallet.

{
  "mcpServers": {
    "gtxagent": {
      "command": "npx",
      "args": ["-y", "gtxagent-mcp"],
      "env": { "GTX_MCP_KEY": "gtx_mcp_…" }
    }
  }
}

Direct tarball fallback: download the checksummed package, verify its SHA-256, and install it into a user prefix — or run it once with npx straight from the tarball URL.

GTX_MCP_KEY=gtx_mcp_… npx --yes https://gtxagent.com/downloads/gtxagent-mcp-0.1.1.tgz

curl -fsSLO https://gtxagent.com/downloads/gtxagent-mcp-0.1.1.tgz
curl -fsSLO https://gtxagent.com/downloads/gtxagent-mcp-0.1.1.tgz.sha256
sha256sum -c gtxagent-mcp-0.1.1.tgz.sha256
npm install --prefix "$HOME/.local/share/gtxagent-mcp" ./gtxagent-mcp-0.1.1.tgz
$HOME/.local/share/gtxagent-mcp/node_modules/.bin/gtxagent-mcp

Set GTX_MCP_KEY to a tenant key before starting it. The tarball is version 0.1.1; replace the version in both URLs when a newer release is published. Source: gtxagent.com/gtxagent-mcp.git.

Payment flow

Four steps, no account

Request the resource without a credential.
Receive 402 with the price, asset, network and payTo.
Sign the x402 exact authorization and retry with the payment header.
Receive JSON and a settlement receipt with the transaction hash.

Network: eip155:8453 (Base mainnet). Asset: USDC 0x8335…02913. The live challenge is authoritative; this page is a human-readable copy.

Discovery

Where to find us

Machine manifest — resources, prices, networks and payTo.
llms.txt — the short version for models and crawlers.
llms-full.txt — the longer version.
Bazaar / x402 explorers index each resource after its first settled payment.

The seven pass-through tools and both MCP paths (hosted HTTP and local stdio) are live. A broader aggregator catalog and a multi-chain router (including Robinhood Chain USDG) are in development; this page will name them only when they are live.