dsh-tool-diff

In AI Agent development or general programming tasks, comparing two pieces of content—such as configuration snippets, API responses, tabular data, or document revisions—is a common need. Traditional methods often rely on spawning external processes to invoke system diff or hand-coding comparison logic, which is not only inefficient (especially on Windows) but also limited: system diff lacks understanding of structured data like JSON or CSV, and custom code is error-prone due to edge cases. The dsh-tool-diff plugin addresses this by offering a lightweight, deterministic solution that makes text comparison straightforward and reliable.

The plugin's core strength lies in its zero-dependency, pure-function, and read-only design. It supports structured comparison across multiple formats: text line-level differences use an efficient Myers algorithm to generate standard unified diff or structured reports with line numbers; JSON comparison recursively detects path-level changes (e.g., $.user.name) and summarizes additions, deletions, or replacements; CSV comparison operates in keyed (by primary key) or positional modes, detailing row and column variations; and Markdown employs a block-level tokenizer to identify differences in headings, code blocks, and other elements. All operations occur in memory without reading or writing files, ensuring security and reproducibility.

Furthermore, the plugin includes patch generation and validation capabilities, allowing it to create unified diffs and verify their correctness in memory, eliminating unnecessary disk I/O. Strict input/output limits prevent performance issues from malicious data. This makes it ideal for AI Agents, automation script developers, or engineers working with structured data who need efficient, accurate text comparison. Whether you're debugging configuration differences, monitoring document changes, or building data processing pipelines, dsh-tool-diff provides a reliable and fast tool for your needs.