Background

When providers add new finish reasons to their API that we do not know about, they get exposed as 'unknown' / 'other'. To enable users to add custom handling until we update the providers, we need to expose the raw finish reason from the provider. This feature is also useful to distinguish mapped finish reasons further, e.g. some providers have several finish reasons that get mapped to a single code.

Summary

• return rawFinishReason from streamText and generateText
• merge unknown finish reason into other
• add raw finish reason to specification
• use PromiseLike in StreamTextResult

Manual Verification

• run examples/ai-core/src/generate-text/openai.ts
• run examples/ai-core/src/stream-text/openai.ts
• run examples/ai-core/src/generate-text/anthropic.ts
• run examples/ai-core/src/stream-text/anthropic.ts

Tasks

• spec
• providers
• functions
• reference docs
• guide docs
• migration guide
• changeset

Future Work

• codemod: removed unknown finish reason
• add rawFinishReason to generateObject, streamObject, streamUI