contextrot

contextrot

Overview

contextrot is a powerful tool designed to assess the performance degradation of coding agents due to context saturation during sessions. It provides personal context-rot analytics that operate 100% locally and require zero configuration. By analyzing session transcripts stored on disk, contextrot identifies when coding agents begin to fail, what causes this decline, and how it impacts productivity.

Key Features

• Local Analysis: contextrot leverages session transcripts to deliver insights without the need for cloud integration, ensuring user privacy and data security.
• Simple Usage: Launch contextrot easily with just a command:

  uvx contextrot
  

• Detailed Reports: Obtain comprehensive reports that outline degradation thresholds, confidence intervals, and recommendations for improvement.

Performance Insight

As coding agents fill their context with information, their performance can suffer, even before reaching known limits. contextrot investigates individual sessions to reveal unique degradation points based on one’s specific projects, models, and interaction styles. This diagnostic tool informs users whether their systems are performing optimally or require adjustments.

Verdicts Provided

Each report from contextrot includes a straightforward verdict:

Verdict	Description
✗ Context rot detected	Indicates a significant increase in failure rate as context fills.
! Edge rot	Remains flat until near context limit, then increases — suggests compacting information before reaching limits.
✓ No measurable rot	The system operates effectively with a consistent failure rate.
? Not enough data	Encourages further usage for additional data collection and analysis.

Comparison with Other Tools

contextrot differs fundamentally from benchmarking tools by focusing on personal usage data rather than synthetic benchmarks. Here’s how it compares against other tools:

Tool	Focus	Limitations
ccusage	Reports usage costs	Does not assess output quality
Claude Code /context	Displays current context content	Lacks historical performance analysis
Langfuse / Phoenix	Analyzes built applications	Requires extensive setup and instrumentation
Chroma's research	Benchmarks degradation	Doesn't reflect personal workload conditions

Reliability and Accuracy

contextrot’s methodology relies on five independent failure signals extracted from coding sessions, including edit failures and retry loops, to provide accurate assessments. Statistics are calculated with conservative confidence intervals to ensure reliable results.

Supported Agents

contextrot currently supports:

• Claude Code (✅ today)
• Future plans for Codex CLI, OpenCode, and others.

Future Developments

Upcoming features include interactive fixes based on reports and support for more agent adapters, contributing to enhanced community insights regarding context rot.

In summary, contextrot serves as an essential tool for understanding and improving the functionality of coding agents, empowered by local data analysis and clear performance insights.