lantern: Instructions file for Claude Code

CLAUDE.md

lantern CLAUDE.md is an instructions file for Claude Code from WildChildForLife/lantern. It costs 1,636 tokens per session, scanned A, a copy of lantern AGENTS.md, MIT.

A project guide for Claude that sets coding, testing, API, commit, and release-note rules for the Lantern codebase.

In plain words
What is it for?
Use it when asking an agent to work on Lantern, especially for implementation, tests, type checking, cleanup, or commits.
Why use it?
It gives an agent the project’s important constraints before it changes code, helping avoid forbidden tools, inconsistent commits, and missed checks.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions subagents.

This is WildChildForLife/lantern's own configuration. It tells Claude Code how to work on lantern itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything lantern configures →

Reuse

Borrowing it

Nothing to install: this file belongs to WildChildForLife/lantern. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/WildChildForLife/lantern/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/WildChildForLife/lantern

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 lantern CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/wildchildforlife/lantern/claude-md.svg)](https://agentmods.dev/instructions/wildchildforlife/lantern/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/wildchildforlife/lantern/claude-md"><img src="https://agentmods.dev/badge/instructions/wildchildforlife/lantern/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,636 This file is loaded in full into every session.
When invoked 1,636 The same file — it is already loaded in full.
Security scan A 1 finding. 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 5.1 $0.01636 $0.01636
Opus 5 $0.00818 $0.00818
Sonnet 5 $0.00327 $0.00327
Haiku 4.5 $0.00164 $0.00164

Measured 6d ago against content hash 10df52943d98, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

lantern CLAUDE.md scanned grade A with 1 finding 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 6d 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.

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

- `Command.string` instead of `child_process`
Origin

This is a copy

86% identical to lantern AGENTS.md — 71 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.

CLAUDE.md · 202 lines

How it starts

The opening of the file, as written. The whole thing — 202 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

Critical Rules (Read First)

Language:

  • Code, comments, commits in English

NEVER:

  • Use as type casting anywhere, tests included (explain problem to user instead)
  • Use raw fetch or bypass TanStack Query for API calls
  • Run pnpm dev or pnpm start (dev servers)
  • Use node:fs, node:path, etc. directly (use Effect-TS equivalents)

ALWAYS:

  • Effect-TS for all backend side effects
  • Hono RPC + TanStack Query for all API calls
  • TDD: tests first, then implement
  • Run pnpm typecheck and pnpm fix before commit

Commit Message Rules

Conventional Commits: type: description

Release Note Awareness:

  • Commit messages ship in release notes. Write for users.

Type Selection:

Type Release Note Purpose
feat Features User-facing new feature
fix Bug Fixes User-impacting bug fix
chore, ci, build, refactor Excluded Internal changes

Critical: fix only for user-facing bugs. Internal fixes (linter errors, type errors, build scripts) use chore.

Message Quality Examples:

  • Bad: fix: fix lingui error (internal issue)
  • Bad: feat: add button (too vague)
  • Good: feat: add dark mode toggle to settings
  • Good: fix: session list not updating after deletion
  • Good: chore: update lingui compiled messages

Project Overview

Lantern reads Claude Code session logs straight from JSONL files (~/.claude/projects/), zero data loss. Web client built as CLI tool serving Vite app.

Core Architecture:

  • Frontend: Vite + TanStack Router + React 19 + TanStack Query
  • Backend: Hono (standalone server) + Effect-TS (all business logic)
  • Data: Direct JSONL reads, strict Zod validation
  • Real-time: Server-Sent Events (SSE) for live updates

Project aims for fast feedback AND code quality (checks pass = runtime correctness near-guaranteed) via:

Read the full file on GitHub · 202 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. 6d ago First seen · 202 lines · 1,636 tokens per session scan A 10df52943d98

Subscribe to this mod's changes

lantern CLAUDE.md is an instructions file published in the GitHub repository WildChildForLife/lantern (28 stars, last pushed today), licensed MIT. It adds 1,636 tokens to every session, about $0.0082 per session on Opus 5. A static security scan graded it A with 1 finding (runs shell commands). It is 86% identical to lantern AGENTS.md, differing in 71 lines, and is treated as a copy.

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