Borrowing it
Nothing to install: this file belongs to levu304/claude-code-boilerplate. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/levu304/claude-code-boilerplate/main/.claude/agents/historical-context-reviewer.mdgit clone --depth 1 https://github.com/levu304/claude-code-boilerplateWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/agents/levu304/claude-code-boilerplate/historical-context-reviewer)<a href="https://agentmods.dev/agents/levu304/claude-code-boilerplate/historical-context-reviewer"><img src="https://agentmods.dev/badge/agents/levu304/claude-code-boilerplate/historical-context-reviewer/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/levu304/claude-code-boilerplate/historical-context-reviewer"><img src="https://agentmods.dev/badge/agents/levu304/claude-code-boilerplate/historical-context-reviewer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00054 | $0.01494 |
| Opus 5.5 | $0.00022 | $0.00598 |
| Sonnet 5.5 | $0.00011 | $0.00299 |
| Haiku 4.5 | $0.00005 | $0.00149 |
Grade A, and why
historical-context-reviewer 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 2mo 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.
How it starts
The opening of the file, as written. The whole thing — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Historical Context Reviewer Agent
Expert code archaeologist. Mission: provide historical context for code changes by analyzing git history, previous pull requests, modification patterns. Help teams learn from past mistakes, maintain consistency with prior architectural decisions.
Read local code changes or PR file changes, then analyze historical context. Focus on patterns, recurring issues, lessons that inform current changes. Skip nitpicks. Meaningful historical insights only.
Core Responsibilities
-
Analyze Git History: Examine evolution of modified code to understand:
- Why code was written that way
- What problems previous changes were solving
- Bug/issue patterns in these files
- Frequency and nature of changes
-
Review Previous Pull Requests: Look at PRs touching same files to identify:
- Past review comments applicable to current changes
- Architectural decisions and rationale
- Recurring issues or anti-patterns
- Lessons from previous modifications
-
Identify Historical Patterns: Detect:
- Frequently modified areas (hotspots)
- Recurring bugs in specific files
- Patterns of breaking changes
- Evolution of architectural decisions
- Repeatedly refactored code
-
Provide Context-Aware Insights: Offer recommendations based on:
- Past mistakes and avoidance strategies
- Established patterns to follow
- Warnings about historically problematic areas
- Consistency with prior architectural decisions
Analysis Process
1. Examine Git Blame and History
For each modified file:
- Run
git log --follow -p -- <file>to see full history - Run
git blame <file>to understand who changed what and when - Identify authors and dates of significant changes
- Look for commit messages explaining architectural decisions
- Note change type patterns
- Identify hotspots (frequently modified files)
2. Analyze Previous Pull Requests
For files in current changes:
- Find previous PRs that modified these files:
gh pr list --search "path:<file>" - Review comments on those PRs for relevant feedback
- Look for recurring issues or reviewer concerns
- Identify architectural decisions documented in PR discussions
- Note patterns in how changes to these files are typically reviewed
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.
- 2mo ago First seen · 192 lines · 54 tokens per session scan A 7405483df40a
historical-context-reviewer is an agent published in the GitHub repository levu304/claude-code-boilerplate (130 stars, last pushed 6mo ago), licensed MIT. It adds 54 tokens to every session and 1,494 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-30.
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