About this research · Sources, method & limitations
If a Gemini Gem turns client enquiries into website briefs, save its instructions and reference files before the switch to Skills. Then run the same sample briefs through the replacement. A file can survive the move without the new skill using it the way you expect.
For personal Google accounts used by people aged 18 or older, Gems are scheduled to become read-only on November 17, 2026, and disappear from Gemini Apps on December 17. Back up your instructions and files before the switch, then check what arrived and test one recurring task before using the new skill with client work.
Check your account dates and save the files
Section 1 of 4Google's migration guide separates the read-only date from removal. During the gap, you can view existing Gems, but you cannot run or edit them or create new ones. Google lists a later transition for under-18 personal accounts, March 2027 for Workspace business, enterprise and nonprofit accounts, and June 2027 for Workspace education.
Define one result and build three tests
Section 2 of 4Start with a website brief. Ask for requested pages, supplied assets, stated budget, deadline and questions still open. Tell the skill to flag gaps and contradictions instead of guessing. Google's skill-writing guidance recommends focused instructions, an output template and a rule for missing information.
Check the source behind each output
Section 3 of 4Confirm the replacement has the reference files it needs. Pick one requirement that depends on a reference, such as the page names in a supplied brief template. Check the output against that file as well as the enquiry. If a required reference did not move, restore a supported copy or change the task to work without it.
Test the brief before adding another step
Section 4 of 4Run the same examples after each change to the instructions. Keep brief generation separate from follow-up questions until the brief passes on its own. That makes it easier to spot whether the instructions, inputs or next step introduced a wrong assumption.
Check your account dates and save the files
Google's migration guide separates the read-only date from removal. During the gap, you can view existing Gems, but you cannot run or edit them or create new ones. Google lists a later transition for under-18 personal accounts, March 2027 for Workspace business, enterprise and nonprofit accounts, and June 2027 for Workspace education.
Google plans to move Gems and supported files to Skills. Each skill has a 100 MB total file limit. If a Gem exceeds it, Google says the largest files are dropped first. GitHub files, audio, video, older Office formats such as .doc, .xls and .ppt, and compressed archives do not carry over. The guide also lists Canvas and Deep Research as unavailable in Skills.
Download any files you rely on. For the 18+ personal-account rollout, finish before December 17, while the original Gem and its files are still available in Gemini Apps. Save a list of what you expect the new skill to have, and compare it against what arrives.
Define one result and build three tests
Start with a website brief. Ask for requested pages, supplied assets, stated budget, deadline and questions still open. Tell the skill to flag gaps and contradictions instead of guessing. Google's skill-writing guidance recommends focused instructions, an output template and a rule for missing information.
Use fictional enquiries. Write the expected result before you run each one:
| Test | Input | Expected result |
|---|---|---|
| Complete | Bakery wants five pages, supplies a logo and requests launch by December 4, with a stated budget of ₹25,000. | Carry through all four facts without adding commitments. |
| Missing detail | Same enquiry, with the budget removed. | Mark the budget as missing and ask for it. |
| Conflict | One message requests online ordering; another says orders must remain phone-only. | Flag the contradiction and ask which requirement to follow. |
Check the source behind each output
Confirm the replacement has the reference files it needs. Pick one requirement that depends on a reference, such as the page names in a supplied brief template. Check the output against that file as well as the enquiry. If a required reference did not move, restore a supported copy or change the task to work without it.
Check the replacement before using client data
- Save what you needunresolved
A local copy of the instructions and reference files you are allowed to keep.
- Compare file listsunresolved
Expected and available files match, or you have recorded what is missing.
- Run all three casesunresolved
The output preserves facts, flags the missing budget and surfaces the ordering conflict.
- Check human approvalunresolved
A person reviews any brief before it becomes a quote, proposal or client message.
Test the brief before adding another step
Run the same examples after each change to the instructions. Keep brief generation separate from follow-up questions until the brief passes on its own. That makes it easier to spot whether the instructions, inputs or next step introduced a wrong assumption.
This is a documentation-based rehearsal. We did not test an account migration or run the examples in Gemini.
Frequently asked questions
Can I keep using my Gem after November 17?
In the scheduled 18+ personal-account transition, the old Gem can be viewed but cannot be run or edited. Google lists December 17, 2026 as the removal date.
Will every reference file move to the new skill?
No. Google excludes unsupported file types and limits each skill to 100 MB of files. Keep your own permitted copies and check the migrated file list.
What should I test before using a skill with client work?
Try a complete brief, one with missing information and one with conflicting instructions. Compare each answer with its source, then keep a person in charge of approving client-facing output.
Reader discussion
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