🟥 🐛 Bug - Invalid URI in 'Related Rule' section breaks the rule

[designbyalex]

Requested by: @designbyalex via YakShaver.ai 🦬
cc: @designbyalex, @adamcogan, @Marxoz, @PothieuG, @Freego1783

Hi Team!

  🟥  Watch the video (2 min 21 sec)

  Url from screen share: https://rules.ssw.com.au

---

Pain

• A Rule breaks (404 error) when a Related Rule contains an invalid URI / slug / path.
• This commonly occurs when a folder name or slug is renamed, but existing Rules still reference the old path.
• The resulting 404 error is misleading and provides no indication of the real issue.
• When a Rule is broken in this way, it cannot be opened or edited in TinaCMS, preventing non-technical users from fixing it.
• The only workaround is a manual fix in GitHub:
  • Locate the correct rule.mdx
  • Identify the invalid Related Rule path
  • Update it to the correct URI

This creates unnecessary friction and blocks content fixes for editors who rely on TinaCMS.

Acceptance Criteria

1. Broken Rules caused by invalid Related Rule URIs can still be opened in the TinaCMS editor.
2. TinaCMS clearly flags invalid URIs / slugs within the Related Rule section.
3. Editors can update and fix invalid URIs / slugs directly in TinaCMS.
4. The system displays a clear and accurate error message indicating that a Related Rule link is broken (instead of a generic 404).

Steps to Reproduce

1. Open any rule.mdx file in GitHub.
2. Add a Related Rule with an invalid or non-existent path.
3. Deploy the change to PROD.
4. Open the Rule on the website and observe the page breaking with a 404.
5. Attempt to open the same Rule in TinaCMS.
6. Confirm that the Rule cannot be edited or fixed via the editor.

Screenshot

Figure: Incorrect path in related rule breaks page, preventing edits.

[PothieuG]

✅ Done - Now we have a warning box showing broken related rules links and a working link to the rule update.