Integrations

The gate is one function call between “the model produced something” and “the user’s phone buzzed”. Each framework already has a place reserved for that decision; the adapters put the gate there. This page shows the whole loop per framework and links the examples in the repository.

Two of the examples need neither the framework nor a network. They import the package by name, read a JSON policy and a day of candidates with the clock taken from each line, and print the same thing every run:

git clone https://github.com/Bubblegunn/proactive-gate && cd proactive-gate
npm ci && npm run build
node examples/mastra/run.mjs
node examples/ai-sdk/run.mjs

Mastra

An output processor. Mastra calls it after the model has produced the message and before anything reaches the user; on a rejection the processor calls abort() with the gate’s reason, and the tripwire response tells the model why the message did not go out.

import { Agent } from "@mastra/core/agent";
import { createGate, defaultChecks, MemoryStore } from "proactive-gate";
import { gateProcessor } from "proactive-gate/mastra";

const gate = createGate({ store: new MemoryStore(), checks: defaultChecks({ dailyLimit: 3, quietHoursFloor: "high" }) });

export const assistant = new Agent({
  id: "calendar-assistant",
  instructions: "Say the one thing the user should be told right now, or answer NONE.",
  model: "openai/gpt-4o-mini",
  outputProcessors: [gateProcessor({ gate, toInput: () => ({ user, candidate }) })],
});

Offline: examples/mastra/ runs ten candidates for two users through a policy with weekly and daily budgets; five go out, and the output names the check that stopped each of the other five. With a model: examples/mastra.ts.

Vercel AI SDK

The send tool has needsApproval: true, and the gate answers every approval request. A denied call carries the reason, so the model can plan around it; an approved call has already consumed the budget.

import { gateToolApproval } from "proactive-gate/ai-sdk";

const approve = gateToolApproval({ gate, toInput: (call) => ({ user, candidate: fromCall(call) }) });
const { approved, reason } = await approve(call);
// addToolApprovalResponse({ id: call.approvalId, approved, reason })

Offline: examples/ai-sdk/ answers nine approval requests under a policy that includes the TCPA preset; one of them is a critical alert at 23:00 that the legal window still refuses, because presets carry no priority bypass. With a model: examples/vercel-ai-sdk.ts.

LangChain and LangGraph

Middleware around the send tool (proactive-gate/langchain): a watched tool call is refused with the gate’s reason as the tool result; other tools pass through. In a graph, the notify node asks the gate before it fires the tool: examples/langgraph.ts.

OpenAI Agents

A tool-input guardrail (proactive-gate/openai-agents): the tripwire fires on a rejection and outputInfo carries the decision, including the surfaces an allowed message may use.

Claude Code

A PreToolUse hook. npx proactive-gate hook --policy policy.json --tool send_message reads the event on stdin and prints a permissionDecision for the matching tool; other tools print nothing. examples/claude-code-hook.json.

Python

The same policy file runs in the Python package (Gate.from_policy), sync or async, and passes the same fixtures. See Python.

Listing the gate where these frameworks live

The texts for a Mastra integrations page and a Vercel AI SDK docs pointer are in docs/integrations/ in the repository. If you maintain a framework and want the gate in its docs, open an issue and the page is yours to review.