apps-script-collector for Claude Code and Codex: log daily market prices in Google Sheets

apps-script-collector is a skill that builds a small collector for recording market prices every day with Google Sheets and Apps Script. It is a single skill with four reference files, published in the author’s public repository. This post covers the problem it solves, who it suits, how to install it and make the first request, and the setup detail that most often leads to wrong numbers.

What problem it solves

Recording a daily closing price sounds like a five-minute job until you try to automate it. You need a sheet with the right tabs, a script that fetches values, a scheduled trigger, and some plan for weekends, holidays, and values that arrive late. Ask an agent for “a stock price collector” without structure and you tend to get code with no written requirements and no installation steps that match what the code actually does.

apps-script-collector fixes the order of work. It first confirms what to collect, where to get it, and when to run, without asking again for values you already gave. Then it writes a PRD, writes the Apps Script code, and writes an installation guide, and it delivers all three files. The PRD’s seven exception-handling rules are implemented directly in the code. Among them, it retries when values arrive late, skips weekends and holidays, and records every situation in a log tab. The installation guide then describes the menus and behavior exactly as the code implements them.

Who it fits

The chapter rates four situations. Three cover most decisions.

Situation	Fit	Reason
Recording daily closing prices for Korean stocks	Good fit	Defaults to a two-stock KRX example
Starting sheet automation without writing code	Good fit	Provides a guide containing only required actions
Collecting exchange rates or indexes	Okay	Requires changes to the code format

If what you want is a summary notification delivered through a chatbot, the chapter points you to a different skill.

Install and first run

The folder README says to register it as a skill in the Claude desktop app. For Claude Code and Codex, download the repository and copy the skill folder.

# The folder README says to register it as a skill in the Claude desktop app
# Claude Code: download the repository in Sources, then copy the skill folder
cp -R claude-playbook/01-hanbit-claude-guidebook/chap5/apps-script-collector ~/.claude/skills/

# Codex: copy the same folder to the agent skills path
cp -R claude-playbook/01-hanbit-claude-guidebook/chap5/apps-script-collector ~/.agents/skills/

You do not need to call it by name. It activates when you ask to accumulate market prices or other data in Google Sheets automatically.

Build an automatic stock price collector in Google Sheets

Using the result takes one paste. You paste the template code into the sheet’s script editor and refresh the sheet, and a collector menu appears. Running its initial setup item once creates the tabs, the headers, and a daily 4 p.m. schedule.

What trips people up

The schedule is only as correct as the sheet’s time zone. The first time you run initial setup, Google asks whether to allow the script to access the sheet. Unless the sheet’s time zone is set to (GMT+09:00) Seoul, 4 p.m. will not mean Korean time, so the collector can run before the market closes and record the wrong value. The same caution applies to holidays. The template’s holiday list starts empty, so it skips only the dates you enter yourself. Also note that the SKILL.md says the code has only been written, so it recommends checking percentage-change support for Korean stocks with the built-in diagnostics menu after you paste it.

Where this comes from

This post adapts part of chapter 03-05 of The Claude Code & Codex Skills Guidebook. The full chapter covers the workflow figure that maps the request to the three delivered files and the table of included files, from the PRD structure and two-stock example to the six-step installation guide template, and the book has 52 more skills like this one. Read the full chapter in The Claude Code & Codex Skills Guidebook on Gumroad.