fix(v3): preserve provider for structured output

[miguelg719]

Summary

• infer provider options from the AI SDK model provider identity
• preserve Anthropic structured output configuration after LLMProvider removes the model prefix
• add a regression test for anthropic/claude-opus-4-8 and a patch changeset

Why

LLMProvider passes the bare claude-opus-4-8 model ID to the Anthropic AI SDK provider. AISdkClient previously inferred the provider only from that bare model ID, so extract() omitted structuredOutputMode: auto and did not opt into Anthropic native structured outputs.

Testing

• pnpm --filter @browserbasehq/stagehand run build:esm
• pnpm --filter @browserbasehq/stagehand run test:core -- packages/core/dist/esm/tests/unit/aisdk-clients.test.js
• pnpm --filter @browserbasehq/stagehand run lint
• mocked HTTP smoke with @ai-sdk/anthropic@2.0.81 confirmed output_config.format.type is json_schema for claude-opus-4-8
• live V3 LOCAL browser smoke: extract() with anthropic/claude-opus-4-8 returned the expected typed product object through Anthropic's API

[changeset-bot]

🦋 Changeset detected

Latest commit: 4353d5b

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

This PR includes changesets to release 3 packages

Name	Type
@browserbasehq/stagehand	Patch
@browserbasehq/stagehand-evals	Patch
@browserbasehq/stagehand-server-v3	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[cubic-dev-ai]

No issues found across 3 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

Architecture diagram

sequenceDiagram
    participant Client as External Caller
    participant LLMProv as LLMProvider
    participant AISdk as AISdkClient
    participant infer as inferProviderName()
    participant Model as LanguageModelV2
    participant SDK as AI SDK (generateObject)

    Client->>LLMProv: getClient("anthropic/claude-opus-4-8")
    LLMProv->>LLMProv: strip "anthropic/" prefix → bare "claude-opus-4-8"
    LLMProv->>AISdk: create with model "claude-opus-4-8"
    Note over LLMProv,AISdk: Model is from AI SDK, not raw string

    Client->>AISdk: createChatCompletion(options)
    AISdk->>AISdk: resolve model.provider from AI SDK model
    AISdk->>infer: inferProviderName(model)
    Note over Model,infer: NEW: Use model.provider (e.g. "anthropic")<br/>instead of model.modelId (e.g. "claude-opus-4-8")
    infer->>Model: access model.provider
    Model-->>infer: "anthropic"
    alt provider exists
        infer->>infer: split "anthropic" by "." → ["anthropic"]
        infer-->>AISdk: "anthropic"
    else provider missing (fallback)
        infer->>Model: access model.modelId
        Model-->>infer: "claude-opus-4-8"
        infer->>infer: split "claude-opus-4-8" by "/" → ["claude-opus-4-8"]
        infer-->>AISdk: undefined
    end

    AISdk->>AISdk: check if provider is "anthropic"
    alt provider is "anthropic"
        AISdk->>AISdk: set structuredOutputMode to "auto"
        AISdk->>SDK: generateObject() with providerOptions.anthropic.structuredOutputMode
        Note over AISdk,SDK: Correctly enables native Anthropic structured outputs
    else provider is not "anthropic"
        AISdk->>SDK: generateObject() without Anthropic options
    end

    SDK-->>AISdk: structured output result
    AISdk-->>Client: completion response

Loading

_{Re-trigger cubic}