Summary

Remove exc_info=True from error logging in plugin framework hot path to eliminate critical performance bottleneck.

Closes: #2064

Problem

Performance profiling revealed the plugin framework was spending ~80% of execution time formatting exception tracebacks that were never displayed or thrown. For a typical plugin hook invocation:

• 0.165ms (80%) - Exception/traceback formatting
• 0.042ms (20%) - Actual plugin execution

The root cause was exc_info=True in logger.error() calls within exception handlers in mcpgateway/plugins/framework/manager.py:284,288, which forced Python to capture and format full stack traces on every error
path, even when:

• No exception was actually raised
• Log level suppressed ERROR messages
• The formatted traceback was never displayed

Changes

Removed exc_info=True parameter from two logger.error() calls in PluginExecutor._execute_hook():

• Line 284: PluginError handler
• Line 288: Generic Exception handler

Exception details are still captured via str(pe) and str(e) in the log message.

Impact

Overall Performance Improvement: 84.9% FASTER

Total execution time reduced from 16.19s to 2.44s across all plugin tests.

Detailed Results

Performance evaluation using cProfile, following the guideline in tests/performance.

Key Highlights

• Best improvements (>94% faster):

  • SPARCStaticValidator_tool_pre_invoke: -95.1%
  • CircuitBreaker_tool_pre_invoke: -94.3%
  • CircuitBreaker_tool_post_invoke: -94.2%
  • Watchdog_tool_pre_invoke: -94.2%
  • Watchdog_tool_post_invoke: -94.2%
  • ResourceFilterExample_resource_post_fetch: -94.2%
  • ResourceFilterExample_resource_pre_fetch: -93.7%

• Typical improvements: 80-85% reduction in execution time

• Minimum improvement: 64.5% (PIIFilterPlugin_prompt_pre_fetch)