Prompt Engineer

Moonfire; Dadri; On-site; INR 1,200,000 - 1,800,000; Full time

Benefits offered by this job

Top-of-the-market pay

5-day working

On-site in Noida

Autonomy and ownership

Job summary

JoyzAI in Noida is seeking a design-focused prompt and conversation designer to own the prompts behind our AI calling agent and chatbot. You will translate client requirements into voice-first flows, maintain guardrails, and ensure the agent speaks in English or Hinglish.

You will test transcripts, run experiments, and iterate rapidly with clients and engineering to improve lead qualification rates and user experience. This is a hands-on, high-impact role in a fast-growing startup.

Qualifications

• Worked at a Voice AI company with real clients and production agents.
• Shipped prompts and iterated using live conversation data.

Responsibilities

• Design prompts and script conversations for voice-first interactions.
• Build and maintain prompts behind core workflows (lead qualification, FAQs, bookings).
• Test transcripts and logs daily to catch hallucinations and improve accuracy.
• Run A/B tests and experiments to measure improvements in qualification and drop-offs.
• Document prompt frameworks and reusable templates for future work.

Skills

Voice AI experience

Prompt design

Conversation design

NLP basics

Analytics reading

Tools

LLMs

Conversation platforms

Job description

You'll be the person who makes our AI agents sound right — and convert. At JoyzAI, that means owning the prompts and conversation design behind every client's AI calling agent and chatbot: how the agent opens a call, how it qualifies a lead, how it handles "I'm busy, call me later," how it declines a question it shouldn't answer, and how it does all of that in the client's voice, in English or Hinglish.

This is not a prompt-tweaking role. It's a design-and-own role. You write the prompt, you listen to the calls it produced, you find where it broke, and you fix it — for real clients, in production, with real leads on the other end of the line.

What you'll do

Prompt & conversation design

• Translate each client's business requirements into prompt strategies, conversation flows, and guardrails for their AI calling agent and chatbot.
• Design voice-first conversations — greetings, one-question-per-turn flows, objection handling, voicemail/no-answer/silence fallbacks, and handoffs to WhatsApp for links and addresses.
• Build and maintain the prompts behind core workflows: lead qualification, FAQs, appointment booking, and follow-up sequences.
• Nail tone and persona for each client, including Hinglish where their customers speak it.

Testing & optimisation

• Read call transcripts and chat logs every day. Catch the weak answers, the hallucinations, the places the agent talks too much or asks two questions at once.
• Run structured experiments — A/B prompt variants, regression test sets, edge‑case scripts — and measure what actually moved: qualification rate, drop-offs, escalations, wrong answers.
• Ship prompt improvements fast and safely, without breaking what was already working.
• Document prompt frameworks and reusable templates so the next client's agent starts from a better baseline than the last.

Clients & the team

• Sit in on kickoffs and go-lives with customer success to understand how the client's sales process actually works before you write a word.
• Work with engineering on what the platform needs — new behaviours, better tooling for testing prompts, model changes.
• Feed what you learn from the logs back to product and sales so the whole company gets smarter about what works on a call.

Roughly 70% of your time is hands-on: writing and testing prompts, reading transcripts, running experiments. The other 30% is with clients and the team — understanding the business behind the agent and figuring out what a better conversation is worth to them. Expect that balance to shift toward the thinking as our testing tooling matures.

We're under 15 people building AI calling agents. This is not a comfortable corporate job. You'll be in the trenches, you'll work hard, and you'll compress ten years of ordinary career growth into two (this means salary growth also, not just more work).

What we're looking for

Two things are non-negotiable. Please apply only if you meet both — they're the first thing we screen for.

• You've worked at a Voice AI company. Professionally, on AI voice agents or conversational voice products. You know what makes a voice conversation actually work: turn‑taking, interruptions, latency, STT/TTS quirks, keeping the agent on track without it sounding robotic.
• You've built AI agents for clients, not for yourself. You've taken a client's requirements, shipped an agent their real customers talked to, and iterated on it using live conversation data. Personal projects, hackathon demos, and coursework don't count.

Beyond that, we don't care much about degrees or years. We care that you can:

• Design prompts and script conversations that hold up under systematic testing, not just in the happy path.
• Work comfortably with LLMs and conversational AI platforms, with a basic grasp of NLP concepts.
• Read analytics and transcripts and turn them into concrete prompt changes with measurable results.
• Write clearly and concisely for business and customer-facing communication, with a good ear for tone and context.
• Gather requirements from PMs, engineers, sales, and clients, and iterate quickly without waiting to be told.
• Think in a structured way, sweat the details, and document what you did so others can build on it.

Nice to have: experience with sales tech, CRM systems, or customer support automation.

Full-time, on-site in Noida.

Why JoyzAI?

Utmost freedom and autonomy — to make decisions. You are the taskmaster, do it the way you think is best. We will only suggest.

Complete responsibility. You are the taskmaster. Take responsibility for it.

Top-of-the-market pay – we reward high performance with the best packages.

5-day working – weekends are yours to recharge.

Work from office in Noida – collaborate, learn, grow with a passionate team.

High-growth startup – opportunity to see first hand how AI brings change and be a part of that.