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The LangChain.js adapter (@deedglass/sdk/langchain)

Tested with @langchain/core 1.2.14 (2026-10-04), including a ToolMessage round trip; the peer range is >=1.2 <2.

import { tool } from '@langchain/core/tools';
import { Deedglass } from '@deedglass/sdk';
import { governTool, deedglassTools } from '@deedglass/sdk/langchain';


const dg = new Deedglass();
const refund = governTool(tool(refundCustomer, { name: 'refund_customer', schema }), { client: dg, connector: 'billing' });
const tools = [refund, ...(await deedglassTools(dg))];
  • governTool(tool, options) rebuilds the tool with the same name, description and schema; its function calls the original invoke only after Deedglass authorizes the call. Invoked with a tool call, it answers a ToolMessage as LangChain does.
  • deedglassTools(client) passes each connector tool’s JSON Schema. LangChain doesn’t validate JSON Schema; Deedglass validates arguments server-side before anything runs.
  • Pending and denied return their sentence as the tool output by default.
  • LangGraph’s interrupt pauses a graph for your own reviewer; Deedglass approvals go to the org’s approvers and are sealed. They compose.