Prompts, instructions, projects, skills: four ways to say what you want

The vendors have four different words for four different things, and members mix them up. A prompt is the ask. Custom instructions are how you always want it to behave. A project is a folder that remembers. A skill is a recipe it can run.

1. The prompt: the ask, this once

The message in this chat. It lives once. A well-formed ask carries five things, in any order: your role, the task, the context (or a pointer to the files), the format you want back, and the constraints. That is a paragraph, not a discipline; nobody needs a course in it.

2. Custom instructions: how it always behaves

Standing preferences that apply to every chat: “answer in Macedonian unless I write in English; be brief; ask before assuming.” ChatGPT calls them custom instructions, and notes that a project’s own instructions override the global ones - which is exactly what you want.

3. The project: a folder that remembers

A container with its own files, chats and instructions. ChatGPT: projects keep related chats, files and instructions together. Claude: self-contained workspaces with their own chat histories and knowledge bases. Gemini: a Gem, which you name, give instructions to follow, and give files for context. Microsoft Copilot: how projects and shared context work depends on your organisation’s set-up; ask IT what is enabled.

4. The skill: a recipe it can run

In Claude, skills extend what it can do by giving it specialised knowledge and workflows, switched on under Customize, Skills, with built-in ones for spreadsheets, documents, presentations and PDFs. For a PM the natural custom skill is “the status report”: raw notes in, the board’s format out, every time. The other three have their own routes to a repeatable procedure - a project’s instructions do most of the same work - and the names change; the idea does not.

Which to use when

The one-project-per-project rule

1. Make one workspace per real project

   Not one for “work”. One per project, named after it.

2. Upload the four documents once

   The charter, the WBS, the last report, the anonymised stakeholder list - the context stack.

3. Write the instructions once

   “You help me run the {project}. Reports go to the {sponsor role}, in Macedonian, one page. Ask before assuming.”

4. From then on, just ask

   Every question is already in context. Monday’s message is “here are this week’s notes”.