vercel/ai `2be4fb5e..f3787486`

base and head as given

Experimental language-model middleware is now available from Core
Middleware authors can use Core’s re-exported provider language-model types

files changed: 23
in a component: 5
lines in components: 128
components: 3
public routes changed: 0
schema statements: 0
new dependencies: 0
excluded by role: 18

Where to focus your review

Review the new exported surface2 components with export changes. Check compatibility and intended visibility.
Verify behavior in dependent codeFollow the import paths below and exercise the consumers they reach.

Based on 5 of 5 eligible changed files

Language-model middleware

Added

Before: did not exist
After: Models can be wrapped with middleware

Developers can transform parameters and intercept generation or streaming when invoking language models. The wrapper preserves model capabilities and lets callers override provider and model identifiers.

In favour

In favour: One wrapper applies consistently to generation and streaming calls
In favour: Transformed parameters reach optional operation wrappers

The model found nothing to weigh against this.

Inspect 5 source files behind this explanation

Files changed in 3 components. Dependencies shown: 1 new, 1 unchanged

unchanged · 1new · 11 component added

1 new dependency between components — Core → Core Middleware

What else could behave differently

5 components · 7 files

These components import changed code, directly or through other files. A traced dependency is a place to review, not a confirmed runtime failure.

Reached 2

Component	Symbol	Cited at	Files	Reached by
Corepackages/ai/core/	Added `Experimental_LanguageModelV1Middleware`1 of 2 changed symbols reaching it	packages/ai/core/middleware/language-model-v1-middleware.ts:8-50	1	none direct · 1 at two steps Trace path Shortest component path from the changed symbol: Core Middleware Core Later steps follow file imports; they do not prove this symbol is called.
Core Middlewarepackages/ai/core/middleware/	Added `Experimental_LanguageModelV1Middleware`1 of 2 changed symbols reaching it	packages/ai/core/middleware/language-model-v1-middleware.ts:8-50	2	2 direct Trace path Shortest component path from the changed symbol: Core Middleware Later steps follow file imports; they do not prove this symbol is called.

Held back 3

Component	Files	Reached by	Resolution
packages/ai/streams/	1	none direct · 1 at three steps	precise
packages/ai/core/generate-text/	2	none direct · 2 at four steps	precise
packages/ai/rsc/stream-ui/	1	none direct · 1 at four steps	precise

Statements 2

Experimental_LanguageModelV1Middleware was added and reached 1 file in Core. 1

language-model-v1-middleware.ts:8-50

Experimental_LanguageModelV1Middleware was added and reached 2 files in Core Middleware. 2

language-model-v1-middleware.ts:8-50

17 reached files belong to no component — tests, docs and config.

Routes, schema, dependencies

No public URL, no migration and no new package.

Not stated

91 routes were found on files whose role excludes them, so no route is claimed for them.

Inspect components, files and symbols

Component

Core TypesModified

packages/ai/core/types/

1 file · 8 lines

7 dependents

Core Types added the LanguageModelV1, LanguageModelV1CallOptions, LanguageModelV1Prompt, and LanguageModelV1StreamPart exports.

CoreModified

packages/ai/core/

1 file · 1 line

1 dependent

Core MiddlewareAdded

packages/ai/core/middleware/

3 files · 119 lines

1 dependent

Core Middleware added the Experimental_LanguageModelV1Middleware and experimental_wrapLanguageModel exports.

File

Core Typespackages/ai/core/types/

language-model.ts

+8 −0

Corepackages/ai/core/

index.ts

+1 −0

Core Middlewarepackages/ai/core/middleware/

wrap-language-model.ts

+67 −0

Core Middlewarepackages/ai/core/middleware/

language-model-v1-middleware.ts

+50 −0

Core Middlewarepackages/ai/core/middleware/

index.ts

+2 −0

Function

imports what changeddownstream of it, one mark per step

Experimental_LanguageModelV1Middleware()language-model-v1-middleware.ts

reaches 3 components

Experimental_LanguageModelV1Middleware was added and reached 1 file in Streams. 1

language-model-v1-middleware.ts:8-50

Experimental_LanguageModelV1Middleware was added and reached 2 files in Generate Text. 2

language-model-v1-middleware.ts:8-50

Experimental_LanguageModelV1Middleware was added and reached 1 file in Stream UI. 1

language-model-v1-middleware.ts:8-50

Diff

Core Typespackages/ai/core/types/

language-model.ts

8–15

Corepackages/ai/core/

index.ts

6–6

Core Middlewarepackages/ai/core/middleware/

wrap-language-model.ts

1–67

Core Middlewarepackages/ai/core/middleware/

language-model-v1-middleware.ts

1–50

Core Middlewarepackages/ai/core/middleware/

index.ts

1–2

Analysis scope

1370 → 3

1,370
files at head
47
components
3
changed by this change

Where the new files landed

3 new files

New file	Belongs to	Used by	Calls	Serves
packages/ai/core/middleware/3 new files	Core Middlewarenew territory	Core	nothing outside its own component	—

15 added files carry no component — 10 example, 4 docs, 1 test.

3components changed

3reached, not changed

1components added/removed

1dependencies added between components

0dependencies removed between components

0files moved to another path

23 files changed, 10 claims stated. 5 components reached in total.