Error5 reports
Fix ValidationError
in Pydantic Settings
✅ Solution
ValidationError in pydantic-settings often arises when a setting defined in your BaseSettings model lacks a default value and is not provided through environment variables or other configuration sources. To fix this, ensure all required settings have either a default value assigned directly in the model definition (e.g., `setting_name: str = "default_value"`) or are populated via environment variables during runtime. Consider using `field(default=...)` from pydantic for more complex default value assignments.
Related Issues
Real GitHub issues where developers encountered this error:
Dotenv extras silently dropped when their name shares a complex field's prefixJul 13, 2026
Can't have a CliPositionalArg[list[CustomType]]Mar 26, 2026
Parsing of environment variables into Optional Strict variables is not possible.Feb 20, 2026
BaseSettings cannot rely on nested model defaults when no env values existOct 16, 2025
Strictness with BaseSettingsSep 3, 2025
Timeline
First reported:Sep 3, 2025
Last reported:Jul 13, 2026
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View Pydantic Settings Changelog