[Bug] Write operations fail on pages containing bookmark blocks

[fuleinist]

Bug: Write operations fail on pages with bookmark blocks

Summary

Any write operation (notion-update-page, insert_content, replace_content) fails with a validation_error (HTTP 400) on pages that contain Notion bookmark blocks — even when the edit target has nothing to do with them:

"Invalid Notion page or block URL: https://example.com"

Read operations (notion-fetch) work fine. Write operations are blocked entirely.

Steps to Reproduce

1. Create or open a Notion page containing one or more bookmark blocks (the rich-link embed type)
2. Call notion-update-page with any write command targeting unrelated content on the page
3. Observe validation_error referencing one of the bookmark URLs

Expected Behavior

Write succeeds; bookmark blocks should be irrelevant to operations targeting other content on the page.

Actual Behavior

HTTP 400 validation_error, operation blocked entirely. The error references an external URL from a bookmark block, not the target of the edit.

Environment

• MCP server: Remote (https://mcp.notion.com/mcp) via Claude.ai connector
• Observed with remote MCP server — not confirmed if affects self-hosted

Possible Root Cause (speculative)

The write path may be validating all URLs present in the page's block tree (including bookmark block URLs) rather than only the URLs being written. A bookmark's external URL gets checked against Notion's internal URL validation and fails because it's not a Notion internal URL.

The fix likely involves either:

1. Skipping URL validation for bookmark block URLs during write operations
2. Only validating URLs that are being written/modified, not all URLs present in the page

Workaround

Manual edits in Notion UI. notion-fetch unaffected.