[tool] fix: remove duplicate tool initialization

[Tree-Shu-Zhao]

What does this PR do?

This PR fixes a bug where tool initialization code was duplicated, causing tools to be initialized twice and tool schemas to be printed twice during startup, which may lead to confusion.

1. Removed duplicate tool_list initialization in tool_agent_loop.py
   

   verl/verl/experimental/agent_loop/tool_agent_loop.py

   Line 103 in 2e5805f

   tool_list = initialize_tools_from_config(tool_config_path) if tool_config_path else []

2. This also fixes the duplicate JSON schema printing in BaseTool.__init__

The duplicate initialization was causing tools to be initialized twice, which resulted in the tool schema JSON being printed twice during startup.

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Test

This is a simple code cleanup fix. The change removes duplicate code that was causing tools to be initialized and printed twice. Testing:

• Pre-commit checks passed
• Python syntax validation passed
• No new functionality added, existing CI tests cover tool initialization

API and Usage Example

No API changes. This is purely a bug fix that removes duplicate code.

Design & Code Changes

Root Cause:

verl/verl/experimental/agent_loop/tool_agent_loop.py

Lines 98 to 103 in 2e5805f

	tool_list = initialize_tools_from_config(tool_config_path) if tool_config_path else []
	cls.tools = {tool.name: tool for tool in tool_list}
	cls.tool_schemas = [tool.tool_schema.model_dump(exclude_unset=True, exclude_none=True) for tool in tool_list]
	cls.tool_parser = ToolParser.get_tool_parser(config.actor_rollout_ref.rollout.multi_turn.format, cls.tokenizer)
	cls.tool_parser_name = config.actor_rollout_ref.rollout.multi_turn.format
	tool_list = initialize_tools_from_config(tool_config_path) if tool_config_path else []

called initialize_tools_from_config(tool_config_path) twice, causing:

1. Tools to be initialized twice
2. JSON schema to be printed twice

   verl/verl/tools/base_tool.py

   Line 41 in 2e5805f

   print(json.dumps(self.tool_schema.model_dump(exclude_unset=True, exclude_none=True), indent=2))

Fix: Removed the duplicate line 103, keeping only the first initialization at line 98.

Files Changed:

• verl/experimental/agent_loop/tool_agent_loop.py: Removed duplicate tool initialization

Checklist Before Submitting

Important

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• Add unit or end-to-end test(s) to the CI workflow to cover all the code. If not feasible, explain why: Existing CI tests cover tool initialization; this is a simple duplicate code removal.
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[gemini-code-assist]

Code Review

This pull request correctly addresses a bug where tool initialization was performed twice due to a redundant line of code. By removing the duplicate call to initialize_tools_from_config, the issue of tool schemas being printed multiple times at startup is resolved. The change is simple, correct, and improves the startup behavior. I've reviewed the code and have no further comments.