Lesson 06 · Gemini Mastery Pro ~12 min read 3 Gem builds

Gems: your custom Gemini.

Gems are Gemini's answer to Custom GPTs — purpose-built assistants with custom instructions, knowledge sources from your Workspace, and reusable behavior. This lesson walks the build of three real Gems: a Workspace-aware research assistant, an email drafting Gem, and a team-shareable knowledge Gem.

The mental model

Gems are Custom GPTs that already know your Google Workspace.

Where Custom GPTs need you to upload files explicitly, Gems can reference your Drive, your Gmail, your Calendar. The result: assistants that already know your work context without you re-uploading it.

Workflow 01 Build a Workspace-aware research assistant

1

Gem: "My Research Assistant"

A Gem that knows your industry, references your Drive folders, and produces research grounded in your existing materials.

The prompt that works

Setup walkthroughGemini → Gems → Create Gem → Name: "Research Assistant" → Instructions: "You're my research partner for [your industry]. When I ask questions, reference my existing materials in Drive folder [URL] before generating new content. Cite sources."

Best use cases

  • Industry analysts
  • Consultants with existing research libraries
  • Researchers maintaining ongoing knowledge bases
Workspace permissions matter — Gems can only access what your account can access. Verify you've shared the right folders.
Time savings: Re-explaining context: gone.

Workflow 02 Build an email-drafting Gem

2

Gem: "Email Voice"

A Gem that writes emails in your voice with full Gmail context.

The prompt that works

Setup walkthroughCreate Gem → "Email Voice" → Instructions: "You write emails in my voice: conversational, direct, no 'I hope this finds you well.' When I share an email thread or context, use it. Keep replies under 80 words unless I say otherwise."

Best use cases

  • High-volume email writing
  • Maintaining voice consistency
  • Team members covering for each other
  • Anyone who'd otherwise re-type their voice instructions
Gems can reference Gmail but consider privacy. Don't share Gems that have access to private inboxes with teammates.
Time savings: Voice consistency without re-explanation.

Workflow 03 Build a team-shareable knowledge Gem

3

Gem: "Onboarding Buddy"

A Gem that knows your team's docs, processes, and policies. Share with new hires.

The prompt that works

Setup walkthroughCreate Gem → "Onboarding Buddy" → Instructions: "You answer questions about how [Company] works using only the docs in /OnboardingDocs. Cite the specific doc. If unsure, say 'check with your manager.'" → Share with the team.

Best use cases

  • Companies onboarding multiple new hires
  • Knowledge management for fast-changing teams
  • Department-specific Q&A (engineering, marketing, ops)
  • Reducing repeat questions to senior team members
Team-shared Gems need maintenance. Schedule a quarterly review to update instructions and prune outdated source docs.
Time savings: Repeat onboarding questions: massively reduced.

Final challenge: build your first useful Gem

Identify a recurring task you do in Gemini. Build a Gem for it. Spend 15 min on instructions and source folders. Use it for the next week. Notice the quality jump from defaults.

Back to Gemini Mastery → See pricing →

What you can do now

  • Build a Gem with the 4 essential pieces (name, instructions, knowledge sources, examples)
  • Connect Gems to relevant Workspace data (Drive folders, etc.)
  • Decide what belongs in a Gem vs. a one-off chat
  • Share Gems with teammates when appropriate (with privacy awareness)
  • Maintain Gems quarterly — update instructions, prune outdated sources
Pro
Up next in Gemini Mastery

Lesson 7 · Deep Research: when Gemini does the homework for you

Setting up Deep Research workflows, refining the research prompt, evaluating the output, citing sources properly. The feature that competes directly with Perplexity. See pricing →