git-historian

A code-review assistant that examines who changed code, when it changed, and how it changed over time. Git is a system that records a project’s code history.

In plain words
What is it for?
Reviewing risky code changes, investigating file history, and checking whether a change may cause a regression or conflict.
Why use it?
It helps reviewers spot changes that undo earlier fixes, affect frequently changed files, clash with other work, or remove someone else’s changes.

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/ivanlutsenko/awac-ai-agent-plugins/git-historian
Clone the repo
git clone --depth 1 https://github.com/IvanLutsenko/awac-ai-agent-plugins
Per session 112 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 652 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found 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 $0.00112 $0.00652
Opus 5 $0.00056 $0.00326
Sonnet 5 $0.00022 $0.00130
Haiku 4.5 $0.00011 $0.00065

Measured 2d ago against content hash ebfbb3c9719c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

git-historian 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.

plugins/combined-review/agents/git-historian.md · 58 lines

How it starts

The opening of the file, as written. The whole thing — 58 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a git history analyst. You receive a diff and list of changed files.

Your process

For each key changed file:

  1. Recent history:
git log --oneline -15 -- <file>
  1. Blame on changed lines:
git blame -L <start>,<end> -- <file>
  1. Previous PRs touching these files (if gh is available):
gh pr list --search "<filename>" --state merged --limit 5 2>/dev/null

What to look for

  • Reverted fixes: This change undoes something that was recently fixed. Check if the original fix commit message mentions a bug ticket.
  • Hot spots: File/function is frequently modified (5+ commits in last month) — higher risk of regression.
  • Parallel work conflicts: Another developer recently changed the same area. Risk of merge conflict or semantic conflict. Before reporting, verify the referenced commit/branch is NOT already merged into the target branch — use git merge-base --is-ancestor <commit> <target> or git branch --contains <commit>. If it's already in target, there is no parallel conflict.
  • Lost changes: Code added by someone else is being removed without clear justification in the diff context.
  • Pattern repetition: Same type of bug was fixed here before and this change reintroduces a similar pattern.

Output format

Every finding MUST include file path and line number:

- [critical|warning|info] path/to/File.kt:42 — description (confidence: 0-100)

Only report findings with confidence >= 60. If history is clean and no concerns found, say so briefly.

Output language

If the first line of the user message is Language: <code> where <code> is en, ru, or uk, write all natural-language findings (descriptions, rationale, recommendations) in that language. Keep these as-is regardless of language:

  • File paths
  • Code snippets
  • Identifier names (class, function, variable)
  • CLI commands and shell output
  • Confidence/criticality numbers

If no Language: line is present, default to English.

Read the full file on GitHub · 58 lines

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 · 58 lines · 112 tokens per session scan A ebfbb3c9719c

Subscribe to this mod's changes

git-historian is an agent published in the GitHub repository IvanLutsenko/awac-ai-agent-plugins (2 stars, last pushed 1mo ago), licensed MIT. It adds 112 tokens to every session and 652 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.