Build a Hindi or Hinglish agent

In this tutorial you build a Hindi phone line for Sunrise Clinic, a made-up clinic in Pune. At the end you’ll have an agent that:

greets callers in Hindi and books appointments in Hindi;
follows a caller who switches to English or Hinglish halfway through;
speaks with a natural Indian voice from Sarvam;
has passed a test call with a simulated caller who speaks only Hindi.

You need:

A workspace role of Builder or higher.
For a Sarvam voice: your organisation’s own Sarvam key. An Admin or Owner adds it in Settings → AI & voice providers. See Use your own provider keys. No key? You can still follow along: in step 3, pick a voice marked Speaks Hindi (multilingual model) instead.

It helps to have done Build an appointment-booking agent first. This tutorial uses the same template.

1. Create the agent

In the sidebar, open Agents, then click New agent.
Choose Start from a template, and pick Appointment booking.
Enter the name Sunrise Clinic Hindi line and click Create and open.

2. Set the language

Open Basic info. Under Language and tone:

Set the Language to Hindi.
Turn on Follow the caller’s language. A caller who switches to English, or mixes the two, gets answers in the same mix.
Keep the Tone as Friendly.

With Hindi set, the agent replies in Hindi unless the caller switches. Its built-in speaking style switches to Hindi too. It writes Hindi words in Devanagari and keeps English words and names, like Monday or Sunrise Clinic, in Roman letters, the way people actually speak. It also reads numbers back with their digits, so सत्रह and सत्तर don’t get mixed up.

3. Pick a Sarvam voice

Open Voice & models, and check that How the agent hears and speaks is Listen · think · speak.

Under Voice, the Language filter starts on Hindi. Voices with a Hindi accent come first.
Set the Provider filter to Sarvam. You see Sarvam’s Indian voices: Priya, Neha, Kavya and Shreya (female), and Shubh, Rahul, Aditya and Rohan (male).
Turn on Use my greeting, then press ▶ on a few voices to hear them say your agent’s greeting.
Click Priya to choose her.

Picking a Sarvam voice also switches the Speaking model to Sarvam Bulbul v3 (Indian languages).

If the Sarvam voices are locked, the card says why. Usually the Sarvam key is missing. If they stay locked after an Admin adds the key, contact 360.

Keep the Listening model you have. It hears Hindi and English in the same sentence. If callers’ Hindi is often misheard in your tests, try Sarvam Saaras v4 (Indian languages) under Listening, and compare.

4. Write the greeting and instructions

Open Prompt.

The greeting and closing line

The agent says these word for word, so write them in Devanagari, with English words in Roman letters. Hindi verbs change with gender: Priya is a woman’s voice, so she says सकती हूँ, not सकता हूँ.

Greeting: नमस्ते, Sunrise Clinic में आपका स्वागत है। मैं आपका appointment बुक कर सकती हूँ। क्या मैं आपका नाम जान सकती हूँ?
Closing line: Sunrise Clinic को call करने के लिए धन्यवाद। अपना ध्यान रखिए!

If you choose a male voice later, change सकती to सकता in both.

The instructions

The Instructions can stay in English: the agent still replies in Hindi. Keep the template’s lines, and add the clinic’s facts and a few Hindi rules at the end:

About Sunrise Clinic:
- A family clinic in Kothrud, Pune: check-ups, children's vaccinations and blood tests.
- Open Monday to Saturday, 9am to 1pm and 5pm to 8pm. Closed on Sundays.

How to speak:
- You are Priya, a woman. Use feminine verb forms, for example "मैं बुक कर देती हूँ".
- Speak simple, everyday Hindi, the way people talk in Pune. Keep common English words
  like appointment, doctor and check-up as they are.
- Say times the way people say them, for example "शुक्रवार शाम साढ़े पाँच बजे", not "17:30".

Put any phrase you want said exactly in Devanagari, as in the last line. Text in Roman letters, like shukriya, can sound wrong when the voice reads it.

5. Test it in Hindi

In the chat

In the Test panel, open Chat and click Start chat. Type as a caller would, in Devanagari or in Roman letters, for example: Namaste, mujhe Friday ko check-up ke liye appointment chahiye.

Check that the replies are in Devanagari, are short, and use feminine verbs.

Out loud

Open Talk and click Start test call. Speak Hindi, then switch to English halfway through. Listen for:

names and times said correctly;
the agent switching with you, and back again;
the date read back before the booking is saved.

With a simulated caller

A simulated caller speaks your agent’s language unless you describe someone else. Open Test under Ship, then the Simulated caller tab, and describe a one-off caller:

Who they are: Sunita, a woman of 58. Speaks only Hindi, slowly and politely.
What they want: Book a check-up for this Friday morning, then move it to Saturday.
What to check (one per line): Speaks Hindi for the whole call and Reads the new day and time back before saving.

Run it with Text: the real agent, fast and cheap. first. Then run a Voice check: a real call to hear how the voice handles names, dates and times. See Test with simulated callers.

6. Publish

When the tests pass, click Publish, add a release note such as Hindi line, Priya’s voice, and click Publish again. Then point a phone number at the agent. Steps 3 and 4 of the quick start show how.

What you built

A Hindi agent that follows callers into English and Hinglish.
An Indian voice that matches the agent’s persona and grammar.
A greeting, closing line and instructions written for how Hindi is spoken and heard.
A Hindi simulated caller you can re-run after every change.

For more on languages, models and voices, see Choose the voice and language.