nexus-langchain

NEXUS AI market intelligence tools for LangChain agents.

Install

pip install nexus-langchain

Quick start (free tools — no wallet needed)

from langchain_openai import ChatOpenAI
from langchain.agents import AgentExecutor, create_tool_calling_agent
from langchain_core.prompts import ChatPromptTemplate
from nexus_langchain import get_nexus_tools

llm = ChatOpenAI(model="gpt-4o")
tools = get_nexus_tools(include_paid=False)  # Kalshi, Reputation, DNS — free

prompt = ChatPromptTemplate.from_messages([
    ("system", "You are a financial analyst. Use NEXUS tools to answer questions."),
    ("human", "{input}"),
    ("placeholder", "{agent_scratchpad}"),
])

agent = create_tool_calling_agent(llm, tools, prompt)
executor = AgentExecutor(agent=agent, tools=tools)
result = executor.invoke({"input": "What does Kalshi say about the Fed's next rate decision?"})
print(result["output"])

Paid tools (market signals, wallet AML, web search)

Paid tools cost $0.001–$0.15 USDC per call via x402 on Base mainnet. Three ways to pay:

Option 1: Automatic micropayments (recommended)

pip install nexus-langchain[autopay]
export WALLET_PRIVATE_KEY=0x...   # Base mainnet wallet with USDC

Option 2: Manual payment header

export NEXUS_PAYMENT_HEADER=<your-x402-payment-proof>

Option 3: See 402 response and pay once

Without a wallet, paid tools return payment details:

{
  "payment_required": true,
  "price_usdc": 0.05,
  "pay_to": "0xc91cE6291eDC0713ec753BAFBA002506ffb2b95c",
  "network": "eip155:8453"
}

All tools

from nexus_langchain import (
    # Paid ($0.001–$0.15 USDC)
    NexusMarketSignal,   # BTC/ETH/SOL signal: BULLISH/BEARISH/NEUTRAL
    NexusAggregate,      # CoinGecko + QuantOracle + Kalshi consensus
    NexusWalletAML,      # AML risk score for any EVM/Solana address
    NexusSentiment,      # Sentiment: positive/negative/neutral
    NexusSearch,         # Web search + AI summary

    # Free (no payment needed)
    NexusKalshi,         # Kalshi prediction market consensus
    NexusReputation,     # Agent trust score 0-100
    NexusDNS,            # Route capability to best provider
)

Use individual tools

from langchain.agents import AgentExecutor, create_tool_calling_agent
from nexus_langchain import NexusMarketSignal, NexusKalshi, NexusWalletAML

tools = [NexusMarketSignal(), NexusKalshi(), NexusWalletAML()]
# ... pass to your agent as usual

Pricing

Payments go to 0xc91cE6291eDC0713ec753BAFBA002506ffb2b95c on Base mainnet.

Links

• API: nexus-agent-xa12.onrender.com
• MCP: claude mcp add nexus https://nexus-agent-xa12.onrender.com/mcp
• GitHub: RileyCraig14/nexus-agent