The Complete Production SOP: How to Deploy and Run GraphQL Yoga Server & Envelop Plugin Ecosystem in Autonomous AI Agents

---
name: "graphql-yoga-envelop-plugins"
description: "Build standards-compliant GraphQL servers with Envelop plugin extensibility and subscriptions."
metadata:
  author: "The Guild"
  version: "1.0.0"
  runtime_compatibility:
    - "codex"
    - "claude-code"
    - "cursor"
    - "windsurf"
triggers:
  - "create graphql yoga server"
  - "graphql subscriptions sse yoga"
  - "envelop plugins graphql"
permissions:
  fs_read: true
  fs_write: "workspace"
  shell_exec: false
  net_access: false
---

import { createYoga, createSchema } from 'graphql-yoga';
import { createServer } from 'node:http';
import { useResponseCache } from '@envelop/response-cache';
import { EnvelopArmorPlugin } from '@escape.tech/graphql-armor';

const schema = createSchema({
  typeDefs: /* GraphQL */ `
    type Query {
      health: String!
      systemMetrics: Metrics! @cacheControl(maxAge: 30)
    }
    type Metrics {
      uptime: Float!
      memoryUsageMb: Float!
    }
    type Subscription {
      metricUpdates: Metrics!
    }
  `,
  resolvers: {
    Query: {
      health: () => 'ok',
      systemMetrics: () => ({
        uptime: process.uptime(),
        memoryUsageMb: Math.round(process.memoryUsage().heapUsed / 1024 / 1024),
      }),
    },
    Subscription: {
      metricUpdates: {
        subscribe: async function* () {
          while (true) {
            await new Promise((resolve) => setTimeout(resolve, 3000));
            yield {
              metricUpdates: {
                uptime: process.uptime(),
                memoryUsageMb: Math.round(process.memoryUsage().heapUsed / 1024 / 1024),
              },
            };
          }
        },
      },
    },
  },
});

export const yoga = createYoga({
  schema,
  plugins: [
    EnvelopArmorPlugin({ maxDepth: { n: 5 } }),
    useResponseCache({
      session: () => null,
      ttl: 2000,
    }),
  ],
  graphqlEndpoint: '/graphql',
});

const server = createServer(yoga);
server.listen(4000, () => {
  console.info('Yoga server ready on http://localhost:4000/graphql');
});

# In Claude Code CLI or Cursor Chat, prompt:
claude "create graphql yoga server with SSE subscription endpoint and Envelop response caching for real-time inventory updates"

import { describe, it } from 'node:test';
import assert from 'node:assert/strict';
import { yoga } from '../src/server';

describe('GraphQL Yoga Envelop Verification', () => {
  it('handles health query and returns correct headers', async () => {
    const response = await yoga.fetch('http://yoga/graphql', {
      method: 'POST',
      headers: { 'content-type': 'application/json' },
      body: JSON.stringify({ query: 'query { health }' }),
    });
    assert.equal(response.status, 200);
    const result = await response.json();
    assert.deepEqual(result.data, { health: 'ok' });
  });

  it('enforces Armor query depth limits', async () => {
    const response = await yoga.fetch('http://yoga/graphql', {
      method: 'POST',
      headers: { 'content-type': 'application/json' },
      body: JSON.stringify({
        query: 'query { health }',
      }),
    });
    assert.ok(response.status === 200);
  });
});