release: 4.2.0

[stainless-app]

Automated Release PR

4.2.0 (2026-03-02)

Full Changelog: v4.1.0...v4.2.0

Breaking Changes

• Removed priority parameter and response field from contracts — the priority field is no longer accepted as an input or returned in contract responses.

Features

• Minimum config support for percentage and tiered percentage overwrites — you can now specify a minimum_config when defining percentage and tiered percentage overwrite rates.
• minimum_config added to rates and commits — the minimum_config field is now available on rate and commit objects, along with specialized override tier types.
• subscription_id field on invoice line items — invoice line item objects now include a subscription_id field.
• Compound group keys supported in /v1/usage/groups — the usage groups endpoint now supports compound group keys for more granular usage aggregation.
• New package endpoints — the SDK has been updated to include new package endpoints.

Bug Fixes

• Request cancellation during retry wait — fixed an issue where a request could not be canceled while it was waiting to retry.
• NullStruct serialization — the encoder now correctly serializes NullStruct values.

Docs

• Added missing documentation descriptions across several API fields.

[stainless-app]

🤖 Release is at https://github.com/Metronome-Industries/metronome-python/releases/tag/v4.2.0 🌻