How I Built an AI Email Assistant (And Used AI to Build It)

JamieJamie
7 min read

A developer's journey through IMAP hell, API chaos, and the irony of using Claude to build an email automation platform

The Problem That Started It All

Your inbox is exploding. Customer support emails pile up faster than you can respond. Each email thread becomes a maze of back-and-forth messages that takes 20 minutes just to understand.

That's exactly where I found myself six months ago. But instead of hiring more support staff, I decided to build something different—an AI system that could handle email responses intelligently.

What I didn't expect? How technically brutal it would become. Or how meta the whole experience would be when I started using Claude.ai to help me build an AI email platform.

The Technical Maze: IMAP, Threading, and Email Chaos

Wrestling with Email Protocols

Anyone who's worked with email programmatically knows the truth: emails are messy. Really, really messy.

IMAP seemed straightforward until reality hit. I was suddenly dealing with:

  • Threading nightmares: Emails don't come with neat conversation IDs

  • Encoding chaos: Different clients, different character encodings

  • Attachment scatter: Files spread across MIME parts randomly

  • Server quirks: Each provider implements IMAP just slightly differently

Here's the PHP code I wrote to handle email threading (after many failed attempts):

function buildEmailThread($messageId, $imapConnection) {
    $thread = [];
    $references = getEmailReferences($messageId);

    // Walk backwards through references
    foreach ($references as $ref) {
        $relatedEmails = imap_search($imapConnection, 
            'HEADER Message-ID "' . $ref . '"');

        if ($relatedEmails) {
            $thread[] = parseEmailContent($relatedEmails[0]);
        }
    }

    return array_reverse($thread); // Chronological order
}

The real challenge wasn't just parsing—it was maintaining context across fragmented conversations while keeping response times under 30 seconds.

Dynamic Loading: Speed vs Complexity

With thousands of emails to process, I needed dynamic content loading that wouldn't kill the user experience. This meant coordinating JavaScript and PHP in real-time.

I built a queue-based system where emails get processed in manageable batches:

class EmailProcessor {
    constructor() {
        this.processingQueue = [];
        this.batchSize = 10;
    }

    async processEmailBatch() {
        const batch = this.processingQueue.splice(0, this.batchSize);

        const promises = batch.map(email => 
            this.sendToAIProcessor(email)
        );

        const results = await Promise.all(promises);
        this.updateUI(results);

        // Continue processing if queue has more
        if (this.processingQueue.length > 0) {
            setTimeout(() => this.processEmailBatch(), 100);
        }
    }
}

Building AI with AI: The Meta Experience

Here's where things got surreal. While building Hi AI, I found myself constantly turning to Claude.ai for help. I was literally using AI to build an AI platform.

The conversations were hilariously meta:

  • "Claude, how do I make my AI email system smarter?"

  • "Help me debug this IMAP issue that's blocking my AI responses"

  • "Write cleaner PHP for my AI processing queue"

Claude became my coding partner, helping me:

  • Debug IMAP nightmares that had me stuck for hours

  • Optimize database queries for email storage

  • Design user interfaces for complex AI workflows

  • Refactor messy code when my functions got too nested

But this taught me something important: AI development amplifies human creativity rather than replacing it. Claude couldn't understand my business goals or user needs, but it could help me implement solutions way faster once I knew what I wanted to build.

The API Integration Nightmare (And How I Solved It)

Multiple AI Models, Multiple Headaches

Instead of relying on one AI model, I integrated three: GPT-4, Gemini, and DeepSeek. Each has different strengths:

  • GPT-4: Best for complex reasoning and nuanced responses

  • Gemini: Excellent at context and consistency

  • DeepSeek: Surprisingly good at technical support

But three APIs meant triple the complexity:

  • Different rate limits: Each service throttles differently

  • Different response formats: JSON structures that almost match

  • Different speeds: GPT-4 takes 3 seconds, Gemini takes 1.5

  • Different failure modes: Three ways everything can break

Here's the abstraction layer that saved my sanity:

class AIModelManager {
    private $models = ['gpt4', 'gemini', 'deepseek'];
    private $fallbackChain = [];

    public function generateResponse($emailContent, $preferredModel = 'gpt4') {
        try {
            return $this->callModel($preferredModel, $emailContent);
        } catch (APIException $e) {
            // Fallback to next available model
            foreach ($this->fallbackChain as $fallback) {
                try {
                    return $this->callModel($fallback, $emailContent);
                } catch (APIException $e) {
                    continue;
                }
            }
            throw new Exception('All AI models unavailable');
        }
    }
}

The Custom Training Flow: 26 Steps to AI Perfection

This is where the platform gets really cool. Instead of expecting users to understand prompt engineering, I built a 26-step guided flow that extracts everything needed to create a custom ChatGPT model.

The flow asks simple questions like:

  • "What's your company's tone? Formal or casual?"

  • "What should your AI never share with customers?"

  • "What are your 5 most common customer questions?"

Each answer gets automatically converted into structured training data. At the end, users click one button and their custom ChatGPT model starts training. No technical knowledge required.

function buildTrainingDataset(userResponses) {
    const trainingSet = {
        system_prompt: generateSystemPrompt(userResponses),
        examples: [],
        constraints: userResponses.constraints,
        tone_guidelines: userResponses.tone
    };

    // Generate example conversations based on user input
    userResponses.commonQuestions.forEach(question => {
        trainingSet.examples.push({
            input: question,
            output: generateExampleResponse(question, userResponses)
        });
    });

    return trainingSet;
}

At the end of those 26 steps, users click one button and boom—their custom ChatGPT model starts training. No technical knowledge required.

Performance Challenges and Solutions

The Speed Problem

Early versions were taking 45+ seconds to process complex email threads. Unacceptable for any real-world use.

I optimized by:

  1. Implementing caching for frequently accessed email content

  2. Pre-processing emails in background jobs

  3. Using CDN delivery for static AI model responses

  4. Database indexing on email metadata fields

Current average response time: 8.2 seconds for complex threads, 2.1 seconds for simple queries.

The Context Problem

Maintaining conversation context across multiple emails while keeping token usage reasonable required some creative solutions:

function optimizeContextForAI($emailThread) {
    $context = [];

    // Include last 3 emails fully
    $recentEmails = array_slice($emailThread, -3);
    foreach ($recentEmails as $email) {
        $context[] = $email['full_content'];
    }

    // Summarize older emails
    $olderEmails = array_slice($emailThread, 0, -3);
    if (!empty($olderEmails)) {
        $summary = summarizeEmailChain($olderEmails);
        array_unshift($context, "Previous conversation summary: " . $summary);
    }

    return implode("\n\n---\n\n", $context);
}

Lessons Learned (The Hard Way)

What I Wish I'd Known Earlier

  1. Email parsing is 70% edge cases: Every email client does something slightly different

  2. AI models have personalities: GPT-4 is verbose, Gemini is concise, DeepSeek is literal

  3. Users want control: The 26-step training flow came from user feedback—they wanted to shape their AI's behavior

  4. Fallbacks are essential: When one API goes down (and they do), you need alternatives ready

The Technical Debt Reality

Building fast meant accumulating technical debt. I'm currently refactoring the IMAP handling system because the original implementation, while functional, doesn't scale well beyond 10,000 emails per day.

The Results (And What's Next)

After six months of development, the platform now:

  • Processes 500+ emails daily across multiple client accounts

  • Maintains 94% response accuracy based on user feedback

  • Reduces average response time from 4 hours to 8 minutes

  • Handles 12 different languages thanks to multi-model integration

Building AI in the Age of AI

The meta-experience of using AI to build AI taught me that the future isn't about AI replacing developers—it's about AI making developers more effective. Claude helped me solve problems faster, but I still had to understand the problems, design the solutions, and make the architectural decisions.

For developers considering AI integration projects:

  1. Start with the email parsing layer first—it's more complex than you think

  2. Plan for multi-model integration from day one—vendor lock-in is real

  3. Build your own abstraction layers—you'll thank yourself later

  4. Expect 3x more edge cases than you initially plan for

  5. Use AI tools to help build AI systems—the irony is worth embracing

The Technical Stack Summary

For those interested in the complete technical implementation:

  • Backend: PHP 8.1 with custom IMAP libraries

  • Frontend: Vanilla JavaScript with dynamic loading

  • Database: MySQL 8.0 with optimized indexing

  • AI APIs: OpenAI GPT-4, Google Gemini, DeepSeek

  • Hosting: Cloud infrastructure with auto-scaling

  • Caching: Redis for email content and AI responses

The journey from "emails are overwhelming" to "AI handles everything" took 6 months of intense development, countless debugging sessions, and yes, many conversations with Claude about how to make it all work better.

But watching that first perfectly crafted AI response get sent to a customer? Worth every minute of IMAP wrestling and API rate limiting frustration.

Want to see the system in action? Check out Hi AI and experience how AI-powered email automation can transform your customer communication workflow.

0
Subscribe to my newsletter

Read articles from Jamie directly inside your inbox. Subscribe to the newsletter, and don't miss out.

Written by

Jamie
Jamie