feat: move to middleware

[c-ehrlich]

Middleware

We are moving the Vercel AI SDK wrapper to the middleware pattern that is encouraged in their docs.

There are two different ways of using it:

1. Using wrapLanguageModel from the Vercel SDK itself: wrapLanguageModel({ model, middleware: [AxiomAIMiddleware({ model })] })
2. We will keep the existing wrapAISDKModel(model) which now calls the new stuff internally. There is no user facing change to this API

There is also axiomAIMiddlewareV1 and axiomAIMiddlewareV2 which can be used if it's not possible to pass the model (which is how we know which middleware version to use) to the function.

Other changes

• add middleware examples
• add typechecking/linting/formatting to all examples
• make tool types work better across v4/v5

[Copilot]

Pull Request Overview

Introduces a middleware system for Axiom AI telemetry that integrates with Vercel's AI SDK middleware architecture. This allows users to either continue using the existing wrapper classes (wrapAISDKModel) or adopt the new middleware approach with wrapLanguageModel and Axiom's middleware functions.

• Adds comprehensive middleware implementation with separate V1/V2 versions and a unified auto-detecting variant
• Maintains backwards compatibility by refactoring wrapper classes to use middleware internally
• Includes extensive test coverage for the new middleware functionality

Reviewed Changes

Copilot reviewed 28 out of 29 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/ai/src/otel/middleware.ts	Core middleware implementation with V1/V2 support and unified auto-detection
packages/ai/src/otel/AxiomWrappedLanguageModelV1.ts	Refactored to use middleware internally while preserving API
packages/ai/src/otel/AxiomWrappedLanguageModelV2.ts	Refactored to use middleware internally while preserving API
packages/ai/test/otel/middleware.test.ts	Comprehensive test suite for middleware functionality
Various test files	Added proper telemetry initialization and cleanup
Example files	Updated to demonstrate new middleware usage patterns

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

Comments suppressed due to low confidence (7)

packages/ai/src/otel/wrapTool.ts:61

• [nitpick] The variable name _error follows the convention for unused variables but may be confusing. Consider using a more descriptive name like _serializationError since this is specifically catching JSON serialization errors.

        } catch (_error) {

packages/ai/src/otel/wrapTool.ts:73

• [nitpick] The variable name _error follows the convention for unused variables but may be confusing. Consider using a more descriptive name like _serializationError since this is specifically catching JSON serialization errors.

          } catch (_error) {

packages/ai/package.json:58

• The version 2.0.0-beta.9 should be verified to exist. Based on my knowledge cutoff in January 2025, I cannot confirm this specific beta version exists.

    "@ai-sdk/anthropicv2": "npm:@ai-sdk/anthropic@2.0.0-beta.9",

packages/ai/package.json:60

• The version 2.0.0-beta.12 should be verified to exist. Based on my knowledge cutoff in January 2025, I cannot confirm this specific beta version exists.

    "@ai-sdk/openaiv2": "npm:@ai-sdk/openai@2.0.0-beta.12",

packages/ai/package.json:72

• The version 5.0.0-beta.28 should be verified to exist. Based on my knowledge cutoff in January 2025, I cannot confirm this specific beta version exists.

    "aiv5": "npm:ai@5.0.0-beta.28",

examples/example-middleware/package.json:9

• The version 2.0.0-beta.12 should be verified to exist. Based on my knowledge cutoff in January 2025, I cannot confirm this specific beta version exists.

    "@ai-sdk/openaiv2": "npm:@ai-sdk/openai@2.0.0-beta.12",

examples/example-middleware/package.json:12

• The version 5.0.0-beta.28 should be verified to exist. Based on my knowledge cutoff in January 2025, I cannot confirm this specific beta version exists.

    "aiv5": "npm:ai@5.0.0-beta.28",