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MailchimpSchemaBehavioral

Required fields removed in PATCH /lists/{list_id} request body: [contact campaign_defaults name permission_reminder email_type_option]

Affected surface
PATCH /lists/{list_id}

What changed

Required fields removed in PATCH /lists/{list_id} request body: [contact campaign_defaults name permission_reminder email_type_option] Affected surface: PATCH /lists/{list_id}. Root cause: endpoint `PATCH /lists/{list_id}`. Detected at Fri, 28 Aug 2026 23:36:26 UTC UTC.

Diff

{
  "path": "PATCH /lists/{list_id}",
  "removed_fields": [
    "contact",
    "campaign_defaults",
    "name",
    "permission_reminder",
    "email_type_option"
  ],
  "schema_path": "PATCH /lists/{list_id} request body"
}

Likely impact

The contract still holds, but observable behavior shifted — defaults, response timing, or rate-limit shaping. Existing code keeps compiling and most calls keep working, but edge cases may differ. Worth a sanity check.

Diff your serializers against the new schema. The diff above shows what moved.

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