How I Built Jarvis: A Personal AI Assistant With Claude Code

I didn’t write a single line of code to build my personal AI assistant. Not one.

And yet Jarvis—that’s what I call it—reads my emails, plans my day, tracks my projects across multiple clients, follows up with contacts I’ve neglected, and runs weekly reviews of my goals. It’s a life operating system running entirely on Claude Code.

If you’ve heard of Claude Code and thought “that’s not for me, I don’t know how to code”… this post is for you. I’m going to show you that Claude Code is absolutely for you, and you don’t need to write code to use it. Claude Code writes the code for you. You just describe what you want in plain English.

Play

What is Jarvis?

Jarvis is my personal AI assistant built on Claude Code. Here’s what it does:

Daily operations:

• Plans my day based on calendar, projects, and priorities
• Triages my email and drafts responses
• Tracks habits and reminds me of commitments

Project management:

• Tracks multiple client projects
• Maintains context on each client’s goals and preferences
• Follows up with contacts I haven’t spoken to

Life management:

• Tracks fitness, health, and relationship goals
• Runs weekly reviews
• Maintains a personal CRM of important contacts

All of this runs through Claude Code in my terminal. No apps. No subscriptions. No complicated integrations. Just me talking to an AI that has access to my files, email, and calendar.

The kicker: I built this entire system through conversation. I told Claude what I wanted, and it figured out how to make it happen.

Why Claude Code is Not Just for Developers

Everyone focuses on the word “Code” in Claude Code. They assume it’s a developer tool.

It is a developer tool. It’s an amazing developer tool. I use it all the time to build actual projects. But that’s not all it is.

Here’s what Claude Code actually is: an AI agent with access to your computer.

When you use Claude on the web at claude.ai, you’re chatting with an AI that can only see what you paste into the chat window. It lives in a box.

Claude Code breaks out of the box. It can:

• Read files on your computer
• Write and edit files
• Create and run scripts
• Execute terminal commands
• Search the web
• Connect to external APIs

This is what makes it an agent rather than a chatbot. It doesn’t just give you advice—it takes action.

And here’s the insight that changed everything for me: you don’t need to know how to code to benefit from Claude Code’s ability to write code.

Think about it. If I want Claude to check my email and summarize unread messages, I don’t need to know how to use the Gmail API. I just say:

“Check my email and summarize any unread messages from the past 24 hours.”

Claude figures out that it needs to use the Gmail API, writes a script to do it, runs the script, and gives me the summary. I didn’t write a line of code. I didn’t even know what API calls were involved.

The code is just implementation detail. Claude handles it.

All Your Work is Code

This is the mental shift that unlocks everything.

Think about what you do at work. Whether you’re in marketing, sales, HR, finance, legal—whatever. A huge portion of your time goes to:

• Reading emails
• Writing responses
• Creating documents
• Updating spreadsheets
• Organizing files
• Scheduling meetings
• Following up with people
• Copying data between apps

All of that administrative work? It can all be done with code.

Task	What Code Does
Read emails	Call Gmail API, parse messages
Write responses	Generate text, call Gmail API to send
Create documents	Generate content, write to file
Update spreadsheets	Parse data, modify cells, save file
Organize files	Read directory, move files, rename
Schedule meetings	Call calendar API, create events
Follow up with people	Query CRM, draft messages, send emails
Copy data between apps	API call to App A, transform, API call to App B

Every single one of these tasks is just a series of API calls and file operations. You’ve been doing them manually because you didn’t have time to write the automation scripts.

Claude Code writes those scripts for you, on demand, in real time.

The question to ask yourself: “Am I doing the same thing I did last week, just with different data?”

If yes, that task can be automated. And you don’t need to know how—you just need to describe what you want.

How Jarvis is Different from ChatGPT

You might be thinking: “ChatGPT can do a lot of this. It connects to Gmail, calendar, etc.”

True. ChatGPT has integrations. But there’s a fundamental difference.

ChatGPT works a certain way. The integrations are pre-built. Gmail integration does what OpenAI designed it to do. Calendar integration works how they built it. If you want something different, too bad.

Claude Code has no predefined way of working. It’s a blank slate AI agent. You tell it how you want it to work, and it figures out how to make that happen.

Example. I wanted this specific workflow:

“Find everyone I haven’t responded to in the past two weeks. For each person, check our conversation history. Check my CRM for context on our relationship. Draft a personalized follow-up in my voice. Update the CRM with the interaction.”

That’s a complex, multi-step workflow that touches Gmail, my CRM (a markdown file), and requires understanding my writing style. No pre-built integration does this.

But Claude Code can. I described what I wanted, and it:

1. Connected to Gmail via API
2. Queried for conversations where I was the last to receive a message
3. Filtered to those older than 2 weeks
4. Read each email thread for context
5. Cross-referenced with my contacts file
6. Drafted personalized follow-ups matching my voice
7. Updated the contacts file with notes

It wrote scripts to automate parts of this. Now I can run it whenever I want with a single command.

That’s the difference. ChatGPT gives you pre-built tools. Claude Code builds custom tools on demand.

How I Built Jarvis: The Full Story

Jarvis wasn’t built in a day. It evolved over weeks of conversation with Claude Code. Let me walk you through exactly how it happened.

Week 1: Basic Task Tracking

I started simple. All I wanted was a way to track my to-dos through conversation.

My prompt:

“I want you to help me track my tasks. When I tell you about something I need to do, add it to a tasks.md file. When I complete something, mark it done. When I ask what I need to do, read the file and tell me.”

What Claude did:

• Created a tasks.md file in my working directory
• Started maintaining a checkbox-style task list
• Read and updated the file whenever I mentioned tasks

Sample output:

# Tasks

## In Progress
- [ ] Finish client proposal for Project X
- [ ] Review PR from Sarah
- [ ] Schedule call with investor

## Completed
- [x] Send invoice to Client A
- [x] Update project timeline

Super simple. But it worked. And it taught me the pattern: describe what you want, let Claude figure out the implementation.

Week 2: Email Integration

Once task tracking worked, I wanted Claude to see my email.

My prompt:

“I want you to be able to read my Gmail. I have a Google Cloud project set up. How do I give you access?”

What Claude did:

• Walked me through enabling the Gmail API
• Helped me create OAuth credentials
• Wrote a script to authenticate and fetch emails
• Stored credentials securely
• Now could fetch my emails on demand

Setting up Gmail access:

# Claude guided me through this process:

# 1. Go to Google Cloud Console
# 2. Create a new project (or use existing)
# 3. Enable Gmail API
# 4. Create OAuth 2.0 credentials
# 5. Download the credentials JSON file

# Claude then wrote a script that:
# - Handles OAuth flow
# - Stores refresh tokens
# - Fetches emails programmatically

Now I could say:

“Check my email for anything urgent from clients.”

And Claude would actually check my email and report back.

Week 3: Calendar Integration

Same pattern for calendar:

My prompt:

“Now I want you to see my Google Calendar too. Same Google account.”

What Claude did:

• Enabled Calendar API using existing credentials
• Extended the auth script to include calendar scope
• Could now read and create calendar events

Now I could say:

“What do I have scheduled tomorrow?”

Or:

“Block 2 hours on Thursday afternoon for deep work.”

And Claude would actually interact with my calendar.

Week 4: Daily Planning

With email and calendar connected, I built my first real workflow.

My prompt:

“I want a morning planning routine. When I say ‘plan my day’, I want you to:

1. Check what day it is
2. Look at my calendar
3. Check my tasks file for open items
4. Check email for anything urgent
5. Give me a prioritized plan for the day”

What Claude did:

• Created a custom command I could invoke
• Combined data from calendar, tasks, and email
• Applied prioritization logic I described
• Output a formatted daily plan

Sample daily plan output:

## Tuesday, January 21, 2026

### Calendar
- 10:00 AM: Standup with Client A team (30 min)
- 2:00 PM: Strategy call with Client B (1 hour)
- 4:30 PM: Coffee chat with Alex

### Top 3 Priorities
1. **Finish Client A proposal** — Due tomorrow, ~2 hours work remaining
2. **Review Sarah's PR** — Blocking her work, quick task
3. **Prep for Client B strategy call** — Review notes, 30 min prep

### Suggested Schedule
- 8:00-10:00: Deep work on Client A proposal
- 10:00-10:30: Standup
- 10:30-11:00: Quick tasks (PR review, emails)
- 11:00-12:00: Buffer/overflow
- 12:00-1:00: Lunch break
- 1:00-1:30: Prep for Client B call
- 2:00-3:00: Client B strategy call
- 3:00-4:00: Follow up on call, update notes
- 4:30-5:00: Coffee with Alex

### Emails Needing Response
- **Sarah (Client A)**: Asking about timeline — URGENT
- **Mike (Investor)**: Follow-up on last meeting — This week
- **Newsletter subscriber**: Question about blog post — When time permits

### Habits to Track
- [ ] Morning exercise
- [ ] Read for 30 min
- [ ] No social media before noon

This was the moment it clicked. I wasn’t just chatting with an AI. I had an actual assistant that knew my schedule, my tasks, and my email.

Week 5-6: Contact Management

Next I wanted to track relationships.

My prompt:

“I want to maintain a personal CRM. Create a contacts.md file where I can track:

• People I work with
• How I know them
• Last interaction date
• Notes about them
• Follow-up reminders

When I have a meeting or email exchange with someone, update their entry.”

What Claude did:

• Created a structured contacts file
• Started updating it based on calendar events and emails
• Could query it: “When did I last talk to [person]?”

Sample contacts file:

# Contacts

## Clients

### Sarah Chen — Client A
- **Role**: Head of Product
- **Company**: TechCorp
- **How we met**: Referral from Mike
- **Last contact**: 2026-01-20 (email about timeline)
- **Notes**:
  - Prefers bullet points over long emails
  - Has two kids, mentions them often
  - Interested in AI agents for customer support
- **Follow up**: Send proposal by Jan 22

### James Wilson — Client B
- **Role**: CTO
- **Company**: StartupXYZ
- **Last contact**: 2026-01-19 (strategy call)
- **Notes**:
  - Very technical, appreciates detailed explanations
  - Budget conscious, needs ROI justification
  - Timezone: PST
- **Follow up**: Send implementation timeline by Jan 25

## Network

### Mike Thompson — Investor
- **How we met**: Introduced by Alex at conference
- **Last contact**: 2026-01-15 (lunch meeting)
- **Notes**:
  - Interested in AI infrastructure plays
  - Has portfolio company that might need consulting
- **Follow up**: Send deck for new project idea

Now Claude could say: “You haven’t talked to Mike in 6 days. He mentioned a portfolio company—want me to draft a follow-up?”

Week 7-8: Life Beyond Work

The system was working so well for work that I expanded it to life.

My prompt:

“I want to track more than just work. Add:

• Fitness goals and workout tracking
• Health habits (sleep, hydration, etc.)
• Relationship priorities (family, friends)
• Personal projects and learning goals

Integrate this into daily planning.”

What Claude did:

• Extended the file structure
• Added habit tracking
• Modified daily planning to include personal goals
• Started weekly reviews

Extended daily plan:

## Tuesday, January 21, 2026

### Life Dashboard
- **Fitness**: Rest day (ran yesterday). Stretch + walk.
- **Health**: Sleep 7.2 hrs (target: 8). Drink more water.
- **Relationships**: Mom's birthday in 3 days — order gift.

### Work Priorities
[... same as before ...]

### Habits to Track
- [ ] 10 min morning stretch
- [ ] 8 glasses of water
- [ ] No screens after 9 PM
- [ ] Call one friend/family member
- [ ] Read 30 min before bed

Today: A Full Operating System

Now, months in, Jarvis is a comprehensive system:

jarvis/
├── CONTEXT.md              # Who I am, how I work
├── daily/
│   ├── 2026-01-21.md       # Today's plan
│   ├── 2026-01-20.md       # Yesterday
│   └── ...
├── projects/
│   ├── client-a/
│   │   ├── CLAUDE.md       # Project context
│   │   ├── notes/
│   │   ├── deliverables/
│   │   └── timeline.md
│   ├── client-b/
│   │   └── ...
│   └── personal/
│       ├── blog/
│       └── course/
├── contacts/
│   ├── clients.md
│   ├── network.md
│   └── personal.md
├── tracking/
│   ├── habits.md
│   ├── fitness.md
│   └── goals.md
├── workflows/
│   ├── plan-day.md
│   ├── email-triage.md
│   ├── weekly-review.md
│   └── follow-up-check.md
└── scripts/               # Auto-generated by Claude
    ├── gmail_client.py
    ├── calendar_client.py
    └── ...

I don’t fully understand everything in the scripts/ folder. Claude wrote it, Claude maintains it. I just describe what I want, and the system works.

Building Your Own Jarvis: Step by Step

Ready to build your own? Here’s exactly how to start.

Step 1: Install Claude Code

If you haven’t already, install Claude Code:

# Install via npm
npm install -g @anthropic-ai/claude-code

# Or download from
# https://claude.ai/code

You’ll need a Claude Pro ($20/month) or Max ($100+/month) subscription.

Run claude in your terminal to start.

Step 2: Create Your Working Directory

mkdir ~/jarvis
cd ~/jarvis

Tell Claude this is your workspace:

“This folder is going to be my personal assistant workspace. I’ll call it Jarvis. Can you create a CONTEXT.md file where I describe who I am and how I work?”

Claude will create the file and interview you to fill it out.

Step 3: Start with Task Tracking

Don’t try to build everything at once. Start with one simple workflow.

“I want to track my tasks. When I mention something I need to do, add it to a tasks.md file. When I say I completed something, mark it done. When I ask what I need to work on, show me the list.”

Practice this for a few days. Get comfortable with the pattern.

Step 4: Add Email Access

When you’re ready for more power, add email:

“I want you to be able to read my Gmail. Walk me through setting up API access.”

Claude will guide you through:

1. Google Cloud Console setup
2. Enabling Gmail API
3. Creating OAuth credentials
4. Authenticating

This takes about 15 minutes the first time.

Step 5: Add Calendar Access

Same process:

“Now add Google Calendar access using the same credentials.”

Now Claude can see your schedule and create events.

Step 6: Build Your First Workflow

Combine everything into a useful routine:

“Create a /plan-day command that:

1. Checks my calendar for today
2. Reads my tasks file
3. Checks email for anything urgent
4. Gives me a prioritized daily plan”

Save this workflow so you can run it every morning.

Step 7: Expand Over Time

From here, expand based on your needs:

• Add contact tracking
• Add project folders
• Add habit tracking
• Create more workflows
• Connect more tools

Each addition is just a conversation with Claude about what you want.

Starter Prompts You Can Use Today

Here are prompts you can copy and use to start building:

Basic Task Management

“Create a tasks.md file in this folder. Whenever I mention a task, add it with a checkbox. When I say I completed something, mark it done. Format it with sections for ‘In Progress’ and ‘Completed’. When I ask what I need to do, read the file and give me a summary.”

Morning Planning

“Every morning when I say ‘plan my day’, I want you to:

1. Check the current date and day of week
2. Read my tasks.md for open items
3. Ask me about any meetings or commitments
4. Create a prioritized list with time estimates
5. Suggest a schedule based on my available time”

Email Summary (once you’ve connected Gmail)

“Check my email from the past 24 hours. Categorize each message as:

• URGENT: Needs response today
• THIS WEEK: Needs response within 7 days
• FYI: No response needed
• ARCHIVE: Can be ignored

For anything URGENT, draft a response for my review.”

Contact Tracking

“Create a contacts.md file. When I mention meeting or talking with someone, check if they’re in the file. If not, ask me about them and add an entry. If yes, update their ‘last contact’ date. Include fields for: name, how I know them, company/role, last contact date, notes, and follow-up reminders.”

Weekly Review

“Every Friday when I say ‘weekly review’, I want you to:

1. Read all my daily plan files from this week
2. Count how many tasks I completed vs planned
3. Check which contacts I interacted with
4. Identify any overdue follow-ups
5. Summarize wins and areas for improvement
6. Ask me to set 3 priorities for next week”

The Mental Shift

Building Jarvis taught me to think differently about AI.

Most people think of AI as ChatGPT: a chat box where you upload content, ask questions, and get answers. Then you go do the actual work yourself.

That’s using AI as a research assistant.

The shift is using AI as an executive assistant.

An executive assistant doesn’t just answer questions. They:

• Take action on your behalf
• Manage your schedule
• Handle your correspondence
• Track your commitments
• Follow up on things you’d forget

Claude Code can do all of this. The only requirement is that you give it access to your systems (files, email, calendar) and describe how you want it to work.

The question to ask: What would I delegate to a human assistant if I had one?

That’s your roadmap for Jarvis.

Common Questions

Do I need to know how to code?

No. I didn’t write any code. Claude writes and maintains all the scripts. You just describe what you want.

Is it secure?

Claude Code runs locally on your computer. Your data isn’t sent to external servers (beyond the Claude API itself). For Gmail/Calendar access, you’re using your own Google Cloud credentials with OAuth.

What if something breaks?

Tell Claude to fix it. “The email script isn’t working—can you debug it?” It will investigate and repair.

How much does it cost?

Claude Pro is $20/month. Claude Max is $100-200/month for heavier usage. Google Cloud APIs are free for personal use at typical volumes.

Can I use this for work?

Yes, but be thoughtful about connecting work email/calendar. Check your company’s policies on third-party AI tools accessing company data.

What’s Next

Jarvis is always evolving. I’m constantly tweaking workflows, adding new capabilities, and refining how it works.

But you don’t need to build something as complex as my setup. Start with one workflow:

• Task tracking
• Daily planning
• Email summaries
• Contact management

Get that working. Live with it for a week. Then expand.

The compound effect is real. What starts as a simple task tracker becomes a full operating system for your work and life.

Claude Code gives you the power. You just have to describe what you want.

Go build something.