Vitest

name: reporters description: Built-in reporters, default selection, and CI/output configuration

Reporters

Select reporters via --reporter or reporters config. Configuring reporters replaces the default list — spread configDefaults.reporters to keep them.

import { configDefaults, defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    reporters: ['verbose', ['junit', { suiteName: 'UI tests' }]],
    // keep defaults and add one:
    // reporters: ['json', ...configDefaults.reporters],
  },
})

Default Selection

When reporters is unset, Vitest auto-selects:

• default for normal terminal runs

• minimal (alias agent) when it detects an AI coding agent — only failed tests + errors, no summary or passing logs, optimized to cut token usage

• github-actions is added when process.env.GITHUB_ACTIONS === 'true'

Built-in Reporters

v4 removed the basic reporter (equivalent to ['default', { summary: false }]). The old verbose flat behavior moved here; use tree for the nested view.

Output Files

v5: the json and junit reporters now write to a file by default (.vitest/json/output.json, .vitest/junit/output.xml) instead of stdout. If you piped output (vitest --reporter=json | jq), read the artifact instead or opt back in with reporters: [['json', { stdout: true }]]. An explicit outputFile is still respected.

vitest --reporter=json --outputFile=./test-output.json

defineConfig({
  test: {
    reporters: ['junit', 'json'],
    outputFile: { junit: './junit.xml', json: './report.json' },
  },
})

JUnit Templating

reporters: [['junit', {
  suiteNameTemplate: '{title}',     // {title} {filename} {basename} {displayName}
  classnameTemplate: '{classname}', // {classname} {title} {suitename} {filename} ...
  titleTemplate: '{title}',
  ancestorSeparator: ' > ',
  addFileAttribute: true,
}]]

{filename} is the relative path (use {basename} for the bare name). Templates can also be functions receiving all variables.

HTML Report (v5 paths)

The HTML reporter writes a directory via outputDir (default .vitest); the entry is <outputDir>/index.html. Use singleFile: true for a self-contained shareable file (large; coverage not inlined).

reporters: [['html', { singleFile: true }]]

Blob & Merge (CI/sharding)

Blobs default to .vitest/blob/. Label environments with VITEST_BLOB_LABEL or the reporter label option:

vitest run --reporter=blob --outputFile=reports/blob-1.json
vitest --merge-reports=reports --reporter=junit --reporter=default

Blob reports don't include file attachments — merge attachmentsDir (.vitest/attachments/) separately. --reporter=blob/--merge-reports don't work in watch mode.

Key Points

• Configuring reporters replaces defaults — spread configDefaults.reporters to keep them

• The minimal/agent reporter is auto-selected for AI agents and minimizes token usage

• Use tree for the nested per-test view (old v3 verbose)

• v5 artifacts (blob, attachments, HTML) live under .vitest/

<!-- Source references: - https://vitest.dev/guide/reporters - https://vitest.dev/config/reporters -->