refactor(env): modernize model configuration environment variables

[quanru]

Summary

This PR refactors the model configuration system with improved naming conventions and better type safety while maintaining backward compatibility for publicly documented environment variables.

Motivation

1. Clearer Naming: Environment variables now follow a consistent MODEL_* pattern instead of OPENAI_*, better reflecting that the system supports multiple model providers
2. Better Semantics: Renamed VL_MODE → LOCATOR_MODE to more accurately describe the element localization mode
3. Improved Type Safety: Separated public and internal type definitions to hide implementation details from users
4. Backward Compatibility: Maintained support for existing documented variables to avoid breaking user configurations

Key Changes

1. Environment Variable Naming Updates

Public API Variables (with backward compatibility):

• OPENAI_API_KEY → MODEL_API_KEY (old name deprecated but still works)
• OPENAI_BASE_URL → MODEL_BASE_URL (old name deprecated but still works)

Locator Mode Variables (VL_MODE → LOCATOR_MODE):

• MIDSCENE_VL_MODE → MIDSCENE_LOCATOR_MODE
• MIDSCENE_VQA_VL_MODE → MIDSCENE_VQA_LOCATOR_MODE
• MIDSCENE_PLANNING_VL_MODE → MIDSCENE_PLANNING_LOCATOR_MODE
• MIDSCENE_GROUNDING_VL_MODE → MIDSCENE_GROUNDING_LOCATOR_MODE

Internal Model Configuration Variables (OPENAI → MODEL):

• MIDSCENE_VQA_OPENAI_API_KEY → MIDSCENE_VQA_MODEL_API_KEY
• MIDSCENE_VQA_OPENAI_BASE_URL → MIDSCENE_VQA_MODEL_BASE_URL
• MIDSCENE_PLANNING_OPENAI_API_KEY → MIDSCENE_PLANNING_MODEL_API_KEY
• MIDSCENE_PLANNING_OPENAI_BASE_URL → MIDSCENE_PLANNING_MODEL_BASE_URL
• MIDSCENE_GROUNDING_OPENAI_API_KEY → MIDSCENE_GROUNDING_MODEL_API_KEY
• MIDSCENE_GROUNDING_OPENAI_BASE_URL → MIDSCENE_GROUNDING_MODEL_BASE_URL
• And default model configuration variables

2. Type System Improvements

Before:

export type TModelConfigFn = (options: { intent: TIntent }) => IModelConfig;

After:

// Public API - intent parameter hidden from users
export type TModelConfigFn = () => IModelConfig;

// Internal type - maintains intent parameter for implementation
/** @internal */
export type TModelConfigFnInternal = (options: { intent: TIntent }) => IModelConfig;

Users no longer see the intent parameter in the public API, making it simpler to use. The parameter is still available internally and can be optionally used by advanced users.

3. Backward Compatibility Implementation

For documented public variables, the system now:

1. Checks for new variable name first (e.g., MODEL_API_KEY)
2. Falls back to legacy name if not found (e.g., OPENAI_API_KEY)
3. Both work seamlessly without breaking existing configurations

Example in decide-model-config.ts:

// When using legacy keys, check for new names first
if (keys.openaiBaseURL === 'OPENAI_BASE_URL' && !openaiBaseURL) {
  openaiBaseURL = provider[MODEL_BASE_URL];
}

Testing

✅ All 24 model-config-manager tests passing
✅ Overall test suite: 241 tests passing
✅ Backward compatibility verified for OPENAI_API_KEY and OPENAI_BASE_URL

Migration Guide

For Users

No immediate action required! Old environment variables continue to work:

• OPENAI_API_KEY and OPENAI_BASE_URL are still supported
• Your existing configurations will work without changes

Recommended (optional): Update to new variable names for better clarity:

# Old (still works)
export OPENAI_API_KEY="sk-..."
export OPENAI_BASE_URL="https://api.openai.com/v1"

# New (recommended)
export MODEL_API_KEY="sk-..."
export MODEL_BASE_URL="https://api.openai.com/v1"

For Contributors

When working with the codebase:

• Use new constant names from packages/shared/src/env/types.ts
• Old constants are marked with @deprecated JSDoc comments
• Tests updated to use new variable names

Files Changed

Core Implementation:

• packages/shared/src/env/types.ts - Type definitions and constants
• packages/shared/src/env/constants.ts - Config key mappings
• packages/shared/src/env/decide-model-config.ts - Compatibility logic
• packages/shared/src/env/model-config-manager.ts - Type casting implementation
• packages/shared/src/env/init-debug.ts - Debug variable updates

Tests:

• Updated all test files to use new variable names
• Added compatibility tests for backward compatibility

Breaking Changes

⚠️ None for documented public API

The following internal variables were renamed directly (no backward compatibility):

• MIDSCENE_VQA_OPENAI_* → MIDSCENE_VQA_MODEL_*
• MIDSCENE_PLANNING_OPENAI_* → MIDSCENE_PLANNING_MODEL_*
• MIDSCENE_GROUNDING_OPENAI_* → MIDSCENE_GROUNDING_MODEL_*

These were never publicly documented and are considered internal implementation details.

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🤖 Generated with Claude Code

Co-Authored-By: Claude [email protected]

[Copilot]

Pull Request Overview

This PR refactors the model configuration system by modernizing environment variable names from OPENAI_* to MODEL_* and VL_MODE to LOCATOR_MODE, improving clarity and semantic accuracy while maintaining backward compatibility for documented public API variables.

Key Changes:

• Renamed public API variables (OPENAI_API_KEY → MODEL_API_KEY, OPENAI_BASE_URL → MODEL_BASE_URL) with backward compatibility
• Updated internal variables from OPENAI to MODEL prefix across all intent types (VQA, planning, grounding)
• Renamed VL_MODE to LOCATOR_MODE for better semantic clarity
• Improved type system by separating public TModelConfigFn from internal TModelConfigFnInternal

Reviewed Changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
packages/shared/src/env/types.ts	Updated type definitions, added new MODEL_* constants, deprecated old OPENAI_* constants, separated public/internal type definitions
packages/shared/src/env/constants.ts	Updated constant mappings to use new MODEL_* and LOCATOR_MODE naming
packages/shared/src/env/decide-model-config.ts	Implemented backward compatibility logic for legacy OPENAI_* variables
packages/shared/src/env/model-config-manager.ts	Added type casting to support internal type while maintaining public API simplicity
packages/shared/src/env/init-debug.ts	Updated debug variable references from DEBUG_AI_* to DEBUG_MODEL_*
packages/shared/tests/unit-test/env/*.test.ts	Updated test files to use new variable names
packages/web-integration/tests/unit-test/*.test.ts	Updated mock configurations to use new variable names
packages/core/tests/unit-test/*.test.ts	Updated test configurations and comments to reflect new naming
packages/android/tests/unit-test/agent.test.ts	Updated mock configuration to use new variable names

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