add support for vertex model provider

[tkattkat]

Why

Adding Vertex AI support to Stagehand.

What changed

• Added GoogleVertexProviderSettings from @ai-sdk/google-vertex to ClientOptions type
• Kept consistent with how we import types from @anthropic-ai/sdk and openai packages
• Fixed typing in model utils

Test plan

• tested locally
• tested existing model format on api

---

Summary by cubic

Adds Vertex AI as a supported provider with typed client options, including service account credentials, and an env var for the API key.

Why:

• Enable Vertex models as a first-class provider.
• Keep client options typing consistent across providers.

What:

• Added Vertex provider to AISDK maps and model creation flow.
• Extended ClientOptions to include GoogleVertexProviderSettings and googleAuthOptions.credentials.
• Updated getAISDKLanguageModel to take ClientOptions directly.
• Mapped env var: GOOGLE_VERTEX_AI_API_KEY.
• Normalized clientOptions typing across agent clients and model utils.
• Added @ai-sdk/google-vertex dependency and changeset entry.

Test Plan:

• Set GOOGLE_VERTEX_AI_API_KEY in your environment.
• Configure a model with provider: "vertex" and a valid Vertex model name; pass any needed clientOptions.
• Optionally pass service account JSON via clientOptions.googleAuthOptions.credentials and verify auth works.
• Call the API and confirm responses; smoke test other providers to ensure no regressions.

^{Written for commit 415d8f4. Summary will update automatically on new commits.}

[changeset-bot]

🦋 Changeset detected

Latest commit: 415d8f4

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@browserbasehq/stagehand	Patch
@browserbasehq/stagehand-evals	Patch

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[greptile-apps]

Greptile Overview

Greptile Summary

Adds Google Vertex AI as a supported model provider alongside existing OpenAI, Anthropic, and other providers. This enables users to leverage Vertex AI models through the AI SDK.

Key Changes:

• Added GoogleVertexProviderSettings to ClientOptions type union for proper Vertex-specific configuration
• Registered vertex provider in AISDK provider maps (AISDKProviders and AISDKProvidersWithAPIKey)
• Added GOOGLE_VERTEX_AI_API_KEY environment variable mapping in providerEnvVarMap
• Improved type safety across the codebase by replacing generic Record<string, unknown> with strongly-typed ClientOptions for all agent clients and model utilities
• Refactored getAISDKLanguageModel to accept ClientOptions object instead of separate apiKey and baseURL parameters for cleaner API
• Fixed Anthropic client to use correct baseURL property name (was incorrectly baseUrl)
• Removed obsolete @ts-expect-error directives that are no longer needed due to improved typing
• Added @ai-sdk/google-vertex dependency (version ^3.0.70) as optional dependency
• Corrected zod peer dependency semver syntax from 3.25.76 || 4.1.8 to ^3.25.76 || ^4.1.8

Impact:
Users can now specify Vertex models using the format vertex/model-name with appropriate client options, following the same pattern as other AISDK providers. The typing improvements provide better autocomplete and compile-time validation for all model provider configurations.

Confidence Score: 5/5

• This PR is safe to merge with no blocking issues - it follows established patterns and improves type safety
• The changes are well-structured and follow the existing pattern for adding new providers. The typing improvements enhance code safety across the entire codebase. The semver syntax fix and removal of @ts-expect-error comments indicate better code health. The Anthropic baseURL fix corrects a typo. All changes are additive (no breaking changes) and have been tested locally per the PR description.
• No files require special attention

Important Files Changed

File Analysis

Filename	Score	Overview
packages/core/lib/v3/types/public/model.ts	5/5	Added GoogleVertexProviderSettings type import and expanded ClientOptions union type to include Vertex provider settings
packages/core/lib/v3/llm/LLMProvider.ts	5/5	Added vertex provider to AISDK provider maps and updated getAISDKLanguageModel to accept ClientOptions instead of separate params
packages/core/lib/modelUtils.ts	5/5	Updated clientOptions return type from generic Record<string, unknown> to strongly-typed ClientOptions
packages/core/lib/utils.ts	5/5	Added GOOGLE_VERTEX_AI_API_KEY environment variable mapping for vertex provider
packages/core/package.json	5/5	Added @ai-sdk/google-vertex dependency and fixed zod semver syntax

Sequence Diagram

sequenceDiagram
    participant User
    participant Stagehand
    participant LLMProvider
    participant getAISDKLanguageModel
    participant createVertex
    participant VertexModel
    
    User->>Stagehand: Initialize with model config
    Note over User,Stagehand: model: "vertex/gemini-1.5-pro"<br/>clientOptions: { apiKey: "..." }
    
    Stagehand->>LLMProvider: getClient(modelName, clientOptions)
    Note over LLMProvider: Detects "/" in model name<br/>Splits into provider & model
    
    LLMProvider->>getAISDKLanguageModel: ("vertex", "gemini-1.5-pro", clientOptions)
    Note over getAISDKLanguageModel: Check if clientOptions provided
    
    getAISDKLanguageModel->>createVertex: createVertex(clientOptions)
    Note over createVertex: Creates Vertex provider with<br/>GoogleVertexProviderSettings
    
    createVertex-->>getAISDKLanguageModel: vertexProvider
    getAISDKLanguageModel->>VertexModel: vertexProvider("gemini-1.5-pro")
    VertexModel-->>getAISDKLanguageModel: languageModel instance
    getAISDKLanguageModel-->>LLMProvider: languageModel
    
    LLMProvider->>LLMProvider: new AISdkClient(languageModel)
    LLMProvider-->>Stagehand: LLMClient instance
    Stagehand-->>User: Ready to use Vertex models

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[greptile-apps]

_{5 files reviewed, 2 comments}

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[cubic-dev-ai]

1 issue found across 6 files

Prompt for AI agents (all 1 issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="packages/core/package.json">

<violation number="1" location="packages/core/package.json:43">
P0: Invalid semver syntax: the caret (`^`) must be placed BEFORE the version number, not after. `3.25.76^` should be `^3.25.76`. This will cause package installation to fail or behave unexpectedly.</violation>
</file>

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[greptile-apps]

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[cubic-dev-ai]

No issues found across 14 files