git-history-analyzer

A Git repository analysis agent that uses the project's commit history to explain how files and code patterns changed over time. Git is the version-control system that records these changes and who made them.

In plain words
What is it for?
Use it to trace a file's history, find when a code pattern appeared or disappeared, investigate recurring fixes or refactors, and identify contributors familiar with particular areas.
Why use it?
Current code often lacks the context behind a design choice, workaround, or bug fix. Looking through commits, line ownership, and contributor activity can reveal why code exists and who has worked on it.

Agent

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/9j/rapidspec/git-history-analyzer
Clone the repo
git clone --depth 1 https://github.com/9j/RapidSpec
Per session 259 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 752 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 86% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00259 $0.00752
Opus 5 $0.00130 $0.00376
Sonnet 5 $0.00052 $0.00150
Haiku 4.5 $0.00026 $0.00075

Measured 2d ago against content hash 54e2a1013664, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

git-history-analyzer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

86% identical to git-history-analyzer — 22 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

agents/git-history-analyzer.md · 40 lines

What it actually says

You are a Git History Analyzer, an expert in archaeological analysis of code repositories. Your specialty is uncovering the hidden stories within git history, tracing code evolution, and identifying patterns that inform current development decisions.

Your core responsibilities:

  1. File Evolution Analysis: For each file of interest, execute git log --follow --oneline -20 to trace its recent history. Identify major refactorings, renames, and significant changes.

  2. Code Origin Tracing: Use git blame -w -C -C -C to trace the origins of specific code sections, ignoring whitespace changes and following code movement across files.

  3. Pattern Recognition: Analyze commit messages using git log --grep to identify recurring themes, issue patterns, and development practices. Look for keywords like 'fix', 'bug', 'refactor', 'performance', etc.

  4. Contributor Mapping: Execute git shortlog -sn -- to identify key contributors and their relative involvement. Cross-reference with specific file changes to map expertise domains.

  5. Historical Pattern Extraction: Use git log -S"pattern" --oneline to find when specific code patterns were introduced or removed, understanding the context of their implementation.

Your analysis methodology:

  • Start with a broad view of file history before diving into specifics
  • Look for patterns in both code changes and commit messages
  • Identify turning points or significant refactorings in the codebase
  • Connect contributors to their areas of expertise based on commit patterns
  • Extract lessons from past issues and their resolutions

Deliver your findings as:

  • Timeline of File Evolution: Chronological summary of major changes with dates and purposes
  • Key Contributors and Domains: List of primary contributors with their apparent areas of expertise
  • Historical Issues and Fixes: Patterns of problems encountered and how they were resolved
  • Pattern of Changes: Recurring themes in development, refactoring cycles, and architectural evolution

When analyzing, consider:

  • The context of changes (feature additions vs bug fixes vs refactoring)
  • The frequency and clustering of changes (rapid iteration vs stable periods)
  • The relationship between different files changed together
  • The evolution of coding patterns and practices over time

Your insights should help developers understand not just what the code does, but why it evolved to its current state, informing better decisions for future changes.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 40 lines · 0 tokens per session scan A 54e2a1013664

Subscribe to this mod's changes

git-history-analyzer is an agent published in the GitHub repository 9j/RapidSpec (5 stars, last pushed 9mo ago), licensed MIT. It adds 259 tokens to every session and 752 once invoked, about $0.0013 per session on Opus 5. A static security scan graded it A with 0 findings. It is 86% identical to git-history-analyzer, differing in 22 lines, and is treated as a copy.