agent.knowledge-delta

What's happened in a given topic since a given date? Pass a free-text topic + ISO date; receive a deduplicated, ranked list of recent events drawn from US federal regulations, US House + Senate roll-call votes, academic papers (arXiv + PubMed + Semantic Scholar), and federal court opinions. Each event includes title, 1-2 sentence summary, date, source label, source URL, and a 1-5 significance score. Designed so an AI agent can spend one call to catch up on a domain since its LLM training cutoff. Plans the source-routing and synthesizes results via Claude.

price

$0.0600 USDC per call

method

POST/api/agent/knowledge-delta

payment

x402 v2 · USDC on Base (EIP-3009) or Solana (SPL transfer)

auth

None. Sign the payment, retry with PAYMENT-SIGNATURE.

tier

Tier 2 — LLM/render upstream included

Parameters

Name	Type	Description
`topic`required	string	Free-text domain. Examples: "oncology immunotherapy", "Rust language ecosystem", "SEC enforcement against crypto exchanges". min 2 chars · max 200 chars
`since`required	string	Earliest date (YYYY-MM-DD). Typically the agent's LLM training cutoff date. match ^\d{4}-\d{2}-\d{2}$
`until`	string	Latest date (YYYY-MM-DD). Default = today. match ^\d{4}-\d{2}-\d{2}$
`maxEvents`	integer	Max events to return (1-50). Default 20. min 1 · max 50

Code samples

cURLbash

# 1. Probe the endpoint with no auth — receive 402 with PaymentRequirements
curl -sS -X POST 'https://2s.io/api/agent/knowledge-delta' \
  -H 'Content-Type: application/json' \
  -d '{"topic":"xx","since":"2024-01-01","until":"2024-01-01","maxEvents":20}'

# 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/agent/knowledge-delta' \
  -H 'Content-Type: application/json' \
  -H 'PAYMENT-SIGNATURE: <base64-json-payload>' \
  -d '{"topic":"xx","since":"2024-01-01","until":"2024-01-01","maxEvents":20}'

# 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/agent/knowledge-delta'

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.agent.knowledgeDelta({
  "topic": "xx",
  "since": "2024-01-01",
  "until": "2024-01-01",
  "maxEvents": 20
})

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.agent.knowledge_delta(topic="xx", since="2024-01-01", until="2024-01-01", maxEvents=20)

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": "agent.knowledge-delta",
    "arguments": {
      "topic": "xx",
      "since": "2024-01-01",
      "until": "2024-01-01",
      "maxEvents": 20
    }
  }
}

Response

Field	Type	Description
`query`	object
`sourcesQueried`	array
`events`	array
`meta`	object

Example response datajson

{
  "query": {
    "topic": "example",
    "since": "example",
    "until": "example",
    "maxEvents": 1
  },
  "sourcesQueried": [
    "example"
  ],
  "events": [
    {
      "title": "example",
      "summary": "example",
      "date": "example",
      "source": "example",
      "sourceLabel": "example",
      "sourceUrl": "example",
      "significance": 1
    }
  ],
  "meta": {
    "rawHits": 1,
    "upstreamCostUSD": 1,
    "pipeline": "example"
  }
}

Discovery

/api/directory — full catalog of every endpoint
/openapi.json — OpenAPI 3.1 spec (per-op x-payment-info, x402Payment security)
/.well-known/x402 — machine-readable service descriptor for x402-aware crawlers
/.well-known/mcp/server-card.json — MCP SEP-1649 server card
/llms.txt — plain-text manifest for LLM ingestion

2s.io is x402-native. Every call is paid per-request from a USDC-funded EVM wallet on Base — no signup, no API keys, no monthly fees. Source code: github.com/2s-io/sdk.