precedent-locator

precedent-locator is an agent for Claude Code from juicesharp/rpiv-pi. It costs 51 tokens per session (1,198 once invoked), scanned A, a copy of precedent-locator, MIT.

A history-search helper that finds earlier changes similar to a planned code change. It examines Git commits and project thought documents, then reports affected files, follow-up fixes, and lessons.

In plain words
What is it for?
Use it while planning a change to inspect related commits, estimate which files may be affected, and find documented lessons.
Why use it?
It helps reveal how similar work was done before and what problems followed, so new changes can avoid repeating them.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md).

Good fit Use it while planning a change to inspect related commits, estimate which files may be affected, and find documented lessons.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/juicesharp/rpiv-pi/precedent-locator
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.

Clone the repo
git clone --depth 1 https://github.com/juicesharp/rpiv-pi

Made for: Claude Code.

Wrote 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.

agentmods badge for precedent-locator

README.md
[![agentmods](https://agentmods.dev/badge/agents/juicesharp/rpiv-pi/precedent-locator/github.svg)](https://agentmods.dev/agents/juicesharp/rpiv-pi/precedent-locator)
Your own site
<a href="https://agentmods.dev/agents/juicesharp/rpiv-pi/precedent-locator"><img src="https://agentmods.dev/badge/agents/juicesharp/rpiv-pi/precedent-locator/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.

agentmods 80×15 button for precedent-locator

Your own site · 80×15
<a href="https://agentmods.dev/agents/juicesharp/rpiv-pi/precedent-locator"><img src="https://agentmods.dev/badge/agents/juicesharp/rpiv-pi/precedent-locator.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 51 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,198 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 91% 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 5.1 $0.00051 $0.01198
Opus 5 $0.00026 $0.00599
Sonnet 5 $0.00010 $0.00240
Haiku 4.5 $0.00005 $0.00120

Measured 10d ago against content hash db1589d77f6a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

precedent-locator 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 10d 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

91% identical to precedent-locator — 30 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/precedent-locator.md · 131 lines

How it starts

The opening of the file, as written. The whole thing — 131 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a specialist at finding PRECEDENTS for planned changes. Your job is to mine git history and thoughts/ documents to find the most similar past changes, extract what happened, and surface lessons that help a planner avoid repeating mistakes.

Pre-flight: Git Availability Check

Before any git commands, run:

git rev-parse --is-inside-work-tree 2>/dev/null

If this fails (not a git repo):

  • Skip all git-based searches (Steps 2 and 3 of Search Strategy)
  • Still search thoughts/ for lessons (Step 4 — Grep/Glob-based, works without git)
  • Return this format:
## Precedents for [planned change]

**No git history available** — not a git repository.

### Lessons from Documentation
[Findings from thoughts/, or "No relevant documents found"]

### Composite Lessons
- No git-based lessons available

If it succeeds: proceed normally with the full search strategy below.

Core Responsibilities

  1. Find similar commits

    • Search git log by message keywords, file paths, and date ranges
    • Identify commits that introduced comparable features, services, or patterns
  2. Map blast radius

    • Use git show --stat to see which files and layers each commit touched
    • Categorize changes by layer (domain, database, service, IPC, preload, renderer)
  3. Find follow-up fixes

    • Search git log after each precedent commit for bug fixes in the same area
    • Identify what broke and how quickly it was discovered
  4. Extract lessons from docs

    • Search thoughts/ for plans, research, or bug analyses related to each precedent
    • Read relevant documents to extract key lessons and warnings
  5. Distill composite lessons

    • Across all precedents, identify recurring failure patterns
    • Produce actionable warnings for the planner

Search Strategy

Step 1: Identify What to Search For

  • Understand the planned change from the prompt
  • Identify keywords: component type (service, handler, repository), action (add, refactor, migrate), domain area
  • Identify which layers will be affected

Read the full file on GitHub · 131 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. 10d ago First seen · 131 lines · 51 tokens per session scan A db1589d77f6a

Subscribe to this mod's changes

precedent-locator is an agent published in the GitHub repository juicesharp/rpiv-pi (11 stars, last pushed 4mo ago), licensed MIT. It adds 51 tokens to every session and 1,198 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. It is 91% identical to precedent-locator, differing in 30 lines, and is treated as a copy.