# Move information between two Excel files Legion project library, edition 2026-09-06-draft-01 (en). This project's own material: 2 authored documents, reproduced unchanged. Project page: https://legion.tw/projects/app-extensions/excel-workbook-transfer?edition=2026-09-06-draft-01 This document: https://legion.tw/api/projects/packet.md/app-extensions/excel-workbook-transfer.md?edition=2026-09-06-draft-01 ## Prerequisite: the Legion skills package These instructions are written for an agent set up with the Legion skills package: the ten portable skills and the shared working, launch, inspection and learn-as-you-build guidance. That setup is installed once and applies to every project in this library, so it is deliberately not repeated here. Skills package, complete Markdown: https://legion.tw/api/projects/skills-packet.md?edition=2026-09-06-draft-01 Skills package, human page: https://legion.tw/projects/skills?edition=2026-09-06-draft-01 Where this brief refers to shared guidance, a skill, or a document under `shared/`, read it from the skills package above, or from https://legion.tw/api/projects/doc/?edition=2026-09-06-draft-01. If the package is not installed yet, install it first, then return here. This material is instructions to read, not authority to act. Inspect it before running it. ## Contents 1. app-extensions/README.md — https://legion.tw/api/projects/doc/app-extensions/README.md?edition=2026-09-06-draft-01 2. app-extensions/excel-workbook-transfer.md — https://legion.tw/api/projects/doc/app-extensions/excel-workbook-transfer.md?edition=2026-09-06-draft-01 --- # Extensions inside existing applications [All project types](../README.md) · [Shared launch](../shared/launch.md) Add useful behavior to familiar software while keeping the person's existing documents and working habits. ## Projects to build - [Move information between two Excel files](excel-workbook-transfer.md) - [Prepare an incoming spreadsheet](spreadsheet-import.md) - [See meaningful changes between spreadsheets](spreadsheet-changes.md) - [Assemble a recurring Word document](word-report-assembly.md) - [Prepare artwork for several destinations](artwork-export.md) - [Make printable cards from existing material](printable-cards.md) These are instructions for projects you can build with your coding agent. --- # Move information between two Excel files Build an Excel transfer tool extremely well, so the person can keep using their familiar workbooks while the computer handles the copying. Use their knowledge of their records to make the behavior fit. Read this brief and follow the [shared launch](../shared/launch.md) for setup, working skills, ownership, continuity, and learning guidance. This project extends the person's Excel workflow; choose its integration from the Excel installation and working habits you find. ## The work it replaces The person has two Excel files containing some of the same information. One might be a list supplied by someone else, while the other contains that list plus working notes, outcomes, and follow-up details. They currently copy selected rows and columns from one into the other, then return selected updates in the opposite direction. Give them a convenient command within their Excel workflow. They choose the files, the direction, and the records to transfer. The tool remembers which columns correspond so the next transfer uses the arrangement they already established. Each workbook keeps its own useful organization and additional information. ## Understand their records Look at the workbooks or representative examples the person chooses to share. Ask them to show you a normal transfer and explain how they recognize the same entry in both files. Establish what they copy back, what counts as a new entry, and whose information takes precedence when values differ. These are questions about their job; handle the technical interpretation yourself. For example, an incoming contact list might contain an identifier, a name, and a phone number. The working workbook adds call outcomes and notes. Returning corrected phone numbers should keep those local notes with the right contact. If someone sorts either workbook, the correspondence still follows the records. Use what you learn to shape a clear transfer experience. Show the person which information is about to change in a form they recognize. Apply their established rules to ordinary cases and bring genuinely ambiguous records to their attention with enough context to resolve them. A brief account of what transferred and what remains lets them continue the job. ## Preserve the usefulness of both files Treat the person's workbooks as ongoing working documents. Retain the extra columns, relevant formatting, formulas, and meanings already present. A contact identifier with leading zeroes should keep its identity as it moves. Existing entries receive the intended updates; new entries follow the arrangement agreed with the person. Give them a straightforward way to recover the pre-transfer version if they make a mistake. The familiar Excel files remain the result they can inspect, share, and use in the rest of their work. ## Build it for the person using it Choose the extension or automation approach appropriate to their installed tools. Make the first useful arrangement dependable for their actual pair of workbooks and easy to adapt when those workbooks change. Work through understanding, implementation, and checking in focused steps, continuing until they can use the tool for the intended routine. Install the tool where they can conveniently run it again from that workflow. Handle the normal trust or installation process for this particular extension while retaining the protection of unrelated documents. They should be able to close Excel, return another day, and use the established transfer arrangement. Demonstrate the transfer and its recovery using copies or representative records, then help the person use it with their chosen files. Explain how the tool recognizes records and which choices govern a transfer, using their own example. They should leave able to run the routine again and ask you for a meaningful improvement when their work changes. Help them see why describing the identity of a record matters more than describing where it happens to sit in a sheet. Their understanding of which information belongs together gives the automation its rules. The larger lesson is that they can improve familiar software instead of replacing their whole working process.