Custom GPTs vs Claude Projects vs Gemini Gems — keeping context for a team
All three solve the same problem: a saved context so you stop pasting the same preamble every day. They differ on how well they share across a team, how much material they hold, and whether anything outside the vendor's ecosystem can reach them.
AI Tools Hub Editorial · published · updated
The short version
- Packaging and distribution, including publicly → Custom GPTs
- Depth on a body of documents → Claude Projects
- Google Workspace files as the source material → Gemini Gems
Side by side
| Custom GPT | Claude Projects | Gemini Gems | |
|---|---|---|---|
| Requires | ChatGPT Plus / Team / Enterprise | Claude Pro / Team / Enterprise | Gemini Advanced / Workspace |
| Instructions | System prompt | Project instructions | Gem instructions |
| Files | Knowledge files | Project files, large | Drive integration plus upload |
| Context depth | Standard | Strongest | Very large |
| External calls | Actions | Tool use / MCP | Via Gemini API |
| Sharing | Store, or internal on Team/Enterprise | Team and Enterprise | Within the Workspace organisation |
| Ecosystem | Largest by far | Growing, business-focused | Tied to Workspace |
Choosing by what you are building
If the goal is a tool many people use — a support assistant, a writing helper for a department — Custom GPTs are the most mature distribution mechanism, and the only one with a public store.
If the goal is depth on a specific body of work — a codebase, a contract set, a research corpus — Claude Projects handle more material and reason over it better, which is the entire point of the long context window.
If the material already lives in Google Drive and your company runs on Workspace, Gems remove the upload step and inherit the permissions you already manage.
Can we move between them?
Instructions port easily; files port with effort; usage habits do not. Choose based on where your team already pays rather than on a feature list.
Are these secure enough for internal documents?
On business plans with training exclusion, generally yes. On individual plans, check the data handling settings first — that is where the exposure is.
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