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mcp/harbor
LangChain

JSON Contracts for LangChain

io.github.json-contracts/json-contracts

JSON contract registry and validator for structured LLM and agent outputs.

client:LangChain transport:stdio runtime:npm

Install JSON Contracts in LangChain

pip install langchain-mcp-adapters 

from langchain_mcp_adapters.client import MultiServerMCPClient

client = MultiServerMCPClient({
        "json-contracts": {
            "transport": "stdio",
            "command": "npx",
            "args": ["-y", "json-contracts"],
        }
})

tools = await client.get_tools()

get_tools() returns the server's tools as LangChain tools, ready for an agent. LangChain docs

JSON Contracts in other clients

JSON Contracts MCP server