$ headless-seo-check http://127.0.0.1:4311 --urls /hreflang-good,/hreflang-drift,/hreflang-dead,/hreflang-drift-dead,/hreflang-html-only --json
--- stdout+stderr ---
headless-seo-check: checking http://127.0.0.1:4311 …
headless-seo-check: 5 of 5 URLs selected, from --urls
{
  "tool": "headless-seo-check",
  "version": "0.1.0",
  "checked_at_unix": 1786210243,
  "interrupted": false,
  "notes": [],
  "fatal": null,
  "site": "http://127.0.0.1:4311",
  "discovery": {
    "source": "--urls",
    "total": 5,
    "checked": 5
  },
  "pages": [
    {
      "url": "http://127.0.0.1:4311/hreflang-good",
      "outcome": "checked",
      "status": 200,
      "ttfb_ms": 0,
      "render_mode": "static",
      "words": 324,
      "internal_links": 17,
      "findings": []
    },
    {
      "url": "http://127.0.0.1:4311/hreflang-drift",
      "outcome": "checked",
      "status": 200,
      "ttfb_ms": 1,
      "render_mode": "static",
      "words": 324,
      "internal_links": 17,
      "findings": [
        {
          "kind": "hreflang-drift",
          "severity": "error",
          "message": "the Link: header and the HTML advertise different URLs for 1 language",
          "detail": [
            "fr  header: http://127.0.0.1:4311/fr/hreflang-drift",
            "fr  HTML:   http://127.0.0.1:4311/fr/slug-traduit",
            "fr  the header target answers HTTP 200"
          ]
        }
      ]
    },
    {
      "url": "http://127.0.0.1:4311/hreflang-dead",
      "outcome": "checked",
      "status": 200,
      "ttfb_ms": 1,
      "render_mode": "static",
      "words": 327,
      "internal_links": 17,
      "findings": []
    },
    {
      "url": "http://127.0.0.1:4311/hreflang-drift-dead",
      "outcome": "checked",
      "status": 200,
      "ttfb_ms": 1,
      "render_mode": "static",
      "words": 327,
      "internal_links": 17,
      "findings": [
        {
          "kind": "hreflang-drift",
          "severity": "error",
          "message": "the Link: header and the HTML advertise different URLs for 1 language",
          "detail": [
            "fr  header: http://127.0.0.1:4311/fr/nexiste-pas",
            "fr  HTML:   http://127.0.0.1:4311/fr/slug-traduit",
            "fr  the header target does not exist (HTTP 404)"
          ]
        },
        {
          "kind": "hreflang-dead-target",
          "severity": "error",
          "message": "1 hreflang target in the Link: header do not exist",
          "detail": [
            "fr  http://127.0.0.1:4311/fr/nexiste-pas — does not exist (HTTP 404)"
          ]
        }
      ]
    },
    {
      "url": "http://127.0.0.1:4311/hreflang-html-only",
      "outcome": "checked",
      "status": 200,
      "ttfb_ms": 1,
      "render_mode": "static",
      "words": 325,
      "internal_links": 17,
      "findings": []
    }
  ],
  "summary": {
    "checked": 5,
    "dynamic": 0,
    "unclear": 0,
    "noindex_header": 0,
    "hreflang_drift": 2,
    "hreflang_dead_target": 1,
    "empty_html": 0,
    "sitemap_errors": 0,
    "unreachable": 0,
    "blocking": 3
  },
  "warnings": 0,
  "exit_code": 1
}
--- exit code: 1 ---