fix(tools): raise ToolUsageError instead of bare raise on non-dict args

[HumphreySun98]

Problem

ToolUsage._original_tool_calling has a bare raise on the non-dict path, which sits outside the preceding try/except:

try:
    arguments = self._validate_tool_input(self.action.tool_input)
except Exception:
    if raise_error:
        raise            # OK — re-raises the active exception
    return ToolUsageError(...)

if not isinstance(arguments, dict):
    if raise_error:
        raise            # BUG — no active exception here
    return ToolUsageError(...)

_tool_calling() calls this with raise_error=True, so if _validate_tool_input ever returns a non-dict, the bare raise fails with RuntimeError: No active exception to re-raise — masking the intended tool-arguments error. It's a latent landmine today (that helper currently always returns a dict or raises), but it's still incorrect.

Fix

Raise the intended ToolUsageError explicitly:

if not isinstance(arguments, dict):
    error = ToolUsageError(f"{I18N_DEFAULT.errors('tool_arguments_error')}")
    if raise_error:
        raise error
    return error

The bare raise at the earlier site (inside except) is correct and left unchanged.

Tests

Added two tests in test_tool_usage.py (mock _validate_tool_input → non-dict): raise_error=True raises ToolUsageError (not RuntimeError), and raise_error=False returns a ToolUsageError. Verified failing-without/passing-with the fix; full test_tool_usage.py (30) green; ruff + mypy clean.

Fixes #6430

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This PR was authored with Claude Code. Per CONTRIBUTING.md, AI-generated contributions require the llm-generated label — I don't have triage permission to set it, so could a maintainer please add it? 🤖 Generated with Claude Code

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ℹ️ Recent review info

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Run ID: 4065675a-9033-4289-aa49-db4ccff5d164

📥 Commits

Reviewing files that changed from the base of the PR and between 289686a and 5a33751.

📒 Files selected for processing (2)

• lib/crewai/src/crewai/tools/tool_usage.py
• lib/crewai/tests/tools/test_tool_usage.py

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📝 Walkthrough

Walkthrough

Fixed a bare raise statement in ToolUsage._original_tool_calling that caused a RuntimeError instead of a meaningful error when tool-validated arguments are not a dictionary. Now a ToolUsageError is explicitly constructed and raised, or returned when raise_error is False. Added corresponding tests.

Changes

Bare raise fix and tests

Layer / File(s)	Summary
Fix bare raise and add regression tests lib/crewai/src/crewai/tools/tool_usage.py, lib/crewai/tests/tools/test_tool_usage.py	When validated arguments are not a dict, a ToolUsageError is now explicitly constructed and raised (instead of a bare raise) when raise_error=True, or returned when raise_error=False; tests import ToolUsageError, add a _tool_usage_for_calling() helper, and verify both branches.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main fix: replacing a bare raise with ToolUsageError for non-dict tool args.
Description check	✅ Passed	The description matches the code changes and explains the bug, fix, and regression tests.
Linked Issues check	✅ Passed	The PR implements the required ToolUsageError behavior and adds tests for both raise_error paths, matching #6430.
Out of Scope Changes check	✅ Passed	The changes stay focused on the bug fix and its tests, with no unrelated code paths or features introduced.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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