Bug: declare "language" key in json object plugin config

[MrZyr0]

Environment

ESLint version: 9.39.0
@eslint/json version: 0.13.2
Node version: v25.0.0
Yarn version: 4.10.3 (PnP)
Operating System: MacOs

Which language are you using?

json

What did you do?

Configuration (`eslint.config.ts`)

import js from "@eslint/js";
import globals from "globals";
import tseslint from "typescript-eslint";
import json from "@eslint/json";
import markdown from "@eslint/markdown";
import { defineConfig } from "eslint/config";

export default defineConfig([
  {
    ignores: [
      "dist/",
      "coverage/",
      "node_modules/",
      ".yarn/",
      ".git/",
    ],
  },
  {
    files: ["**/*.{js,mjs,cjs,ts,mts,cts}"],
    plugins: { js },
    extends: ["js/recommended"],
    languageOptions: {
      globals: globals.node,
      ecmaVersion: 2024,
      sourceType: "module",
    },
    rules: {
      semi: "error",
      "prefer-const": "error",
      "no-console": "warn",
      "no-debugger": "error",
		},
  },
  ...tseslint.configs.recommended,
	{
		files: ["**/*.json"],
		ignores: ["package-lock.json"],
		plugins: { json },
		language: "json/json",
		extends: ["json/recommended"],
	},
	{
		files: ["**/*.jsonc"],
		plugins: { json },
		language: "json/jsonc",
		extends: ["json/recommended"],
	},
	{
		files: ["**/*.json5"],
		plugins: { json },
		language: "json/json5",
		extends: ["json/recommended"],
	},
	{
		files: ["**/*.md"],
		plugins: { markdown },
		language: "markdown/gfm",
		extends: ["markdown/recommended"],
	},
]);

What did you expect to happen?

Just work because it's a vanilla config file generated using command yarn create @eslint/config

What actually happened?

An exception is thrown:

Oops! Something went wrong! :(

ESLint: 9.39.0

TypeError: Key "language": Could not find "json" in plugin "json".
    at new Config (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/lib/config/config.js:415:10)
    at [finalizeConfig] (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/lib/config/flat-config-array.js:212:10)
    at FlatConfigArray.getConfigWithStatus (~/.yarn/berry/cache/@eslint-config-array-npm-0.21.1-c33ed9ec91-10c0.zip/node_modules/@eslint/config-array/dist/cjs/index.cjs:1409:55)
    at FlatConfigArray.getConfig (~/.yarn/berry/cache/@eslint-config-array-npm-0.21.1-c33ed9ec91-10c0.zip/node_modules/@eslint/config-array/dist/cjs/index.cjs:1427:15)
    at entryFilter (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/lib/eslint/eslint-helpers.js:323:27)
    at async NodeHfs.<anonymous> (file://~/.yarn/berry/cache/@humanfs-core-npm-0.19.1-e2e7aaeb6e-10c0.zip/node_modules/@humanfs/core/src/hfs.js:574:24)
    at async NodeHfs.walk (file://~/.yarn/berry/cache/@humanfs-core-npm-0.19.1-e2e7aaeb6e-10c0.zip/node_modules/@humanfs/core/src/hfs.js:614:3)
    at async globSearch (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/lib/eslint/eslint-helpers.js:364:20)
    at async Promise.allSettled (index 0)
    at async globMultiSearch (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/lib/eslint/eslint-helpers.js:455:18)
    at async Promise.all (index 0)
    at async findFiles (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/lib/eslint/eslint-helpers.js:635:25)
    at async ESLint.lintFiles (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/lib/eslint/eslint.js:1014:21)
    at async Object.execute (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/lib/cli.js:428:14)
    at async main (/PROJECT_DIR/.yarn/__virtual__/eslint-virtual-4666e2a0f5/4/.yarn/berry/cache/eslint-npm-9.39.0-32a442bf78-10c0.zip/node_modules/eslint/bin/eslint.js:175:19)

Link to Minimal Reproducible Example

https://stackblitz.com/edit/nestjs-typescript-starter-hqsgwkiv

Participation

• I am willing to submit a pull request for this issue.

Additional comments

No response

[DMartens]

Thank you for taking the time to file an issue.
Unfortunately I cannot reproduce this locally nor on stackblitz.
The linked stackblitz package.json has no dev dependency on @eslint/json, so I get an error about the missing package when running ESLint.
Can you please provide another reproduction and which exact steps you did when creating the configuration.