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Changelog

February 11, 2026
February 11, 2026
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February 9, 2026

1.29.1

(fix): Fix wire tests for paginated endpoints. Previously, wire tests called paginated SDK methods without iterating the returned Pager, so no HTTP request was made and WireMock verification always failed with “Expected 1 requests, found 0”. The generated test now iterates the Pager to trigger the first page request.

1.29.0

(feat): Add support for generating interfaces for all SDK client classes. When generateClientInterfaces: true is configured, each client {ClientName} gets a corresponding {ClientName}Interface with public method signatures. Concrete clients declare implements {ClientName}Interface. This enables standard PHP mocking and DI patterns (PHPUnit::createMock(), Laravel/Symfony DI containers) without requiring concrete class dependencies.

1generators:
2 - name: fernapi/fern-php-sdk
3 config:
4 generateClientInterfaces: true

1.28.0

(feat): Add support for default request parameter values.

When useDefaultRequestParameterValues: true is configured in generators.yml, the SDK will generate default values for query parameters and headers that have defaults defined in the API schema. Parameters with defaults become optional in the constructor, falling back to their default value when omitted.

1generators:
2 - name: fernapi/fern-php-sdk
3 config:
4 useDefaultRequestParameterValues: true