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Introduction

What is PRECC?

PRECC (Sửa lỗi dự đoán cho Claude Code) is a Rust tool that intercepts Claude Code bash commands via the official PreToolUse hook mechanism. It fixes errors before they happen, saving tokens and eliminating retry loops.

Miễn phí cho người dùng cộng đồng.

The Problem

Claude Code wastes significant tokens on preventable mistakes:

  • Wrong-directory errors – Running cargo build in a parent directory that has no Cargo.toml, then retrying after reading the error.
  • Retry loops – A failed command produces verbose output, Claude reads it, reasons about it, and retries. Each cycle burns hundreds of tokens.
  • Verbose output – Commands like find or ls -R dump thousands of lines that Claude must process.

The Four Pillars

Sửa ngữ cảnh (cd-prepend)

Phát hiện khi các lệnh như cargo build hoặc npm test chạy trong thư mục sai và thêm cd /đường/dẫn/đúng && trước khi thực thi.

GDB Debugging

Detects opportunities to attach GDB for deeper debugging of segfaults and crashes, providing structured debug information instead of raw core dumps.

Session Mining

Mines Claude Code session logs for failure-fix pairs. When the same mistake recurs, PRECC already knows the fix and applies it automatically.

Automation Skills

A library of built-in and mined skills that match command patterns and rewrite them. Skills are defined as TOML files or SQLite rows, making them easy to inspect, edit, and share.

How It Works (30-Second Version)

  1. Claude Code is about to run a bash command.
  2. The PreToolUse hook sends the command to precc-hook as JSON on stdin.
  3. precc-hook runs the command through the pipeline (skills, directory correction, compression) in under 3 milliseconds.
  4. The corrected command is returned as JSON on stdout.
  5. Claude Code executes the corrected command instead.

Claude never sees the error. No tokens wasted.

Adaptive Compression

Nếu một lệnh thất bại sau khi nén, PRECC tự động bỏ qua nén ở lần thử tiếp theo để Claude nhận được đầu ra đầy đủ không nén để gỡ lỗi.

Live Usage Statistics

MetricValue
Hook invocations–
Tokens saved–
Saving ratio–%
RTK rewrites–
CD corrections–
Hook latency– ms (p50)

Các con số là ước tính. Mỗi lỗi được ngăn chặn tránh được một chu trình thử lại hoàn chỉnh: đầu ra lỗi, suy luận của mô hình và lệnh thử lại. These numbers update automatically from anonymized telemetry.