Add ignore_args option to tool trajectory evaluation

[abhinavmaddineni]

Problem

When evaluating tool trajectories, the current TrajectoryEvaluator always compares both tool names and arguments (actual.args == expected.args). This applies to all three match types: EXACT, IN_ORDER, and ANY_ORDER.

There are common scenarios where users care only that the correct tools were called (and optionally in the right order), but not about the exact arguments passed. For example:

• Tool arguments are non-deterministic (e.g., generated queries, timestamps)
• The eval focuses on verifying the agent's tool selection strategy, not argument correctness
• Arguments are complex objects where minor formatting differences cause false negatives

Proposed Solution

Add an ignore_args boolean option to ToolTrajectoryCriterion that, when set to True, skips argument comparison entirely and only matches on tool names.

Usage example

{
  "tool_trajectory_avg_score": {
    "threshold": 0.8,
    "match_type": "IN_ORDER",
    "ignore_args": true
  }
}

Scope of changes

1. ToolTrajectoryCriterion — add ignore_args: bool = False field
2. TrajectoryEvaluator — read the flag and conditionally skip arg comparison in all three match methods (EXACT, IN_ORDER, ANY_ORDER)
3. Tests — add coverage for ignore_args=True across all match types, including failure cases and dict-based config

[klateefa]

@abhinavmaddineni Thank you for submitting. It’s currently under review by our team, and I’ll keep you posted on any updates. We appreciate your input!