ai.summarize

Summarize a webpage. POST { url, instruction? }. Returns { url, finalUrl, summary (1-3 sentences), keyPoints (3-7 bullets), title, audience, estimatedReadingMinutes, meta:{ truncated } }. Sibling to /api/ai/extract — use extract when you need a typed payload conforming to your own schema; use summarize when you want a ready-made digest. Supports x402 upto billing: authorize the quoted max, pay only your actual usage.

price
$0.0630 USDC per call
method
POST/api/ai/summarize
payment
x402 v2 · USDC on Base (EIP-3009) or Solana (SPL transfer)
auth
None. Sign the payment, retry with PAYMENT-SIGNATURE.

Overview

The summarize API is a pay-per-call ai endpoint built for AI agents and autonomous software. Summarize a webpage.

There is no signup and no API key. An agent (or any HTTP client) hits the endpoint, receives an x402 "402 Payment Required" challenge, signs a sub-cent USDC payment on Base or Solana, and retries — the data comes back on the paid request. That makes it a drop-in summarize data source for an agent tool-use loop, an MCP host, or a backend that needs ai data on demand without onboarding to yet another vendor portal.

Use cases

Parameters

NameTypeDescription
urlrequiredstring
max 2048 chars · uri
instructionstring
max 1000 chars

Code samples

cURLbash
# 1. Probe the endpoint with no auth — receive 402 with PaymentRequirements
curl -sS -X POST 'https://2s.io/api/ai/summarize' \
  -H 'Content-Type: application/json' \
  -d '{"url":"https://example.com","instruction":"example"}'

# 2. Sign the EIP-3009 transferWithAuthorization for the advertised price +
#    payTo from the 402 envelope, then retry with PAYMENT-SIGNATURE:
curl -sS -X POST 'https://2s.io/api/ai/summarize' \
  -H 'Content-Type: application/json' \
  -H 'PAYMENT-SIGNATURE: <base64-json-payload>' \
  -d '{"url":"https://example.com","instruction":"example"}'

# Or just use the canonical runner — it handles the whole loop:
#   EVM_PRIVATE_KEY=0x... node --env-file=.env.local \
#     --experimental-strip-types scripts/x402-pay.ts \
#     'https://2s.io/api/ai/summarize'
TypeScript / Node — @2sio/sdktypescript
import { TwoS } from '@2sio/sdk'

const client = new TwoS({
  privateKey: process.env.EVM_PRIVATE_KEY as `0x${string}`,
})

const result = await client.ai.summarize({
  "url": "https://example.com",
  "instruction": "example"
})

console.log('endpoint:', result.endpoint)
console.log('cost:', result.costUsd, 'USDC')
console.log('tx:', result.settlement?.txHash)
console.log('data:', result.data)
Python — 2siopython
import os
from twosio import TwoS

client = TwoS(private_key=os.environ["EVM_PRIVATE_KEY"])

result = client.ai.summarize(url="https://example.com", instruction="example")

print("endpoint:", result.endpoint)
print("cost:", result.cost_usd, "USDC")
print("tx:", (result.settlement or {}).get("tx_hash"))
print("data:", result.data)
MCP — Claude Desktop / AgentKit / any MCP hostjson
// 1. Add @2sio/mcp to your MCP host config (Claude Desktop example below).
//    EVM_PRIVATE_KEY funds x402 payments per call.

// claude_desktop_config.json
{
  "mcpServers": {
    "2sio": {
      "command": "npx",
      "args": ["-y", "@2sio/mcp"],
      "env": { "EVM_PRIVATE_KEY": "0x..." }
    }
  }
}

// 2. Once the server is running, agents call this tool via standard MCP:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "ai.summarize",
    "arguments": {
      "url": "https://example.com",
      "instruction": "example"
    }
  }
}
LangChain agent — langchain-twosiopython
# pip install langchain-twosio langchain-anthropic
import os
from langchain_twosio import get_twosio_tools
from langchain_anthropic import ChatAnthropic
from langgraph.prebuilt import create_react_agent

tools = get_twosio_tools(private_key=os.environ["EVM_PRIVATE_KEY"])
llm = ChatAnthropic(model="claude-haiku-4-5", temperature=0)
agent = create_react_agent(llm, tools)

# The agent will pick "twosio_ai_summarize" when the prompt matches.
result = agent.invoke({
    "messages": [("user", "...prompt that requires ai.summarize...")]
})
print(result["messages"][-1].content)
LlamaIndex agent — llama-index-tools-twosiopython
# pip install llama-index-tools-twosio llama-index-llms-anthropic
import asyncio, os
from llama_index_tools_twosio import get_twosio_tools
from llama_index.llms.anthropic import Anthropic
from llama_index.core.agent.workflow import FunctionAgent

tools = get_twosio_tools(private_key=os.environ["EVM_PRIVATE_KEY"])
llm = Anthropic(model="claude-haiku-4-5")
agent = FunctionAgent(tools=tools, llm=llm)

# The agent will pick "twosio_ai_summarize" when the prompt matches.
response = asyncio.run(agent.run("...prompt that requires ai.summarize..."))
print(response)

Response

FieldTypeDescription
okboolean
one of: true
itemsarray
totalintegerTotal matching rows upstream; null when unknown.
sourceobject
Example response datajson
{
  "ok": true,
  "items": [
    {
      "url": "example",
      "finalUrl": "example",
      "summary": "example",
      "keyPoints": [
        "example"
      ],
      "title": "example",
      "audience": "example",
      "estimatedReadingMinutes": 1,
      "truncated": false
    }
  ],
  "total": 1,
  "source": {
    "provider": "example",
    "url": "example",
    "license": "example"
  }
}

FAQ

Do I need an API key to use the summarize API?
No. ai.summarize is x402-native — there is no signup and no API key. Your client makes the call, receives a 402 with payment requirements, signs a USDC payment, and retries. Funds come from a wallet you control.
How much does the summarize API cost?
$0.0630 USDC per call, charged per request. There are no monthly fees, seats, or minimums — you pay only for the calls you make.
Can I try the summarize API for free first?
Yes. Add ?trial=1 (or the header X-2s-Trial: 1) to get a free real call per endpoint per hour, so you can verify the response shape before wiring payment.
Which networks and tokens are supported?
USDC on Base (via EIP-3009 transferWithAuthorization) or Solana (SPL transfer), using the open x402 payment protocol.
How do I call ai.summarize from an AI agent or MCP host?
Use @2sio/sdk (TypeScript), 2sio (Python), or the @2sio/mcp server for any MCP host — each handles the probe → sign → retry loop for you. See the code samples on this page.

Discovery

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