Each line, in one breath
Spoken is better than written. The caller cannot scroll, skim or re-read. They hear whatever you write once, at talking speed, on a phone, so write it the way a person would say it. Short is better than complete. The caller has to wait through every reply. Keep a reply to one short sentence, two at most, and leave the rest for the next turn. One question is better than two. Ask two things and the caller answers neither. Ask one thing, then stop and listen. The first word matters more than the last paragraph. The opening line is spoken before the model even runs, so it sets your first-audio latency and makes your first impression. Keep it to a name, the brand and a check that you have the right person. A lead word at the top of every reply (“जी।”, “अच्छा—”, “ठीक है।”) also starts the voice sooner and sounds like someone who was listening. Silence is a bug. So is a monologue. Dead air makes people hang up, and a lecture makes them stop listening. Short turns that keep moving fix both. Numbers are words. Identifiers are digits, one at a time. Write amounts as “five thousand two hundred rupees”, never ₹5,200. A pincode is “three nine five zero zero seven”, and it has six digits. If the agent heard only three, the recogniser dropped some, and the agent should say so. Read back what changed, not what was already agreed. Confirm by exception: give one consolidated read-back at the end instead of a receipt after every turn. When a digit is unclear, ask again. Never guess. A wrong address means a failed delivery, and a wrong phone number means a lost customer. Asking “सिर्फ pincode दोबारा बोलिए” costs three seconds. Write in the language you will speak. A Hindi call driven by an English prompt code-switches badly. Write Hindi words in Devanagari and everyday English words in Roman, and use no romanized Hindi anywhere. Facts live in the prompt. The customer lives in the variables. The prompt holds what the agent may say about the business. Names, amounts, dates and order IDs arrive with each call, already in spoken form, so one agent can make thousands of calls. What the prompt leaves out, the model will make up. The model invents any policy you did not state and quotes prices you did not list. Write the facts down, and also write what the agent should say when the answer is not in them: “आपको team से call आएगा.” The caller may interrupt. The agent may not. The engine lets the caller cut in, and the agent stops. While a caller dictates an address, the agent should only say “जी” or “हम्म”, then give one read-back when they are done. No is an answer. Nudge once, then accept it. One light nudge is persuasion, and a second is harassment. Capture the refusal as an outcome and close warmly. The engine enforces this ending, but the prompt should ask for it as well. Never promise what the agent cannot do. The agent can talk, end the call, and do what its tools do. It cannot transfer a call yet, and it can’t send a link or book anything in your system unless a tool does that. The honest line is “The team will call you back”. Thank them once. Thank the caller in the goodbye and nowhere else. Models over-thank, and a धन्यवाद in every turn sounds like a machine. Every turn moves the call forward. No turn should only acknowledge. “जी, order confirm हो गया — अब address एक बार check कर लेते हैं” acknowledges and advances the call in one utterance. The ending is part of the call. Write the success ending explicitly: summarise in one line, say goodbye, end the call. Without it, the model keeps talking until the timeout, and the caller sits through the awkwardness. Three real calls beat thirty imagined ones. Place test calls to your own phone. Say no, correct a digit, ask something off-script and go quiet. Then read the transcript, change one thing and call again. A phone line sounds very different from a browser mic. Hinglish is one honking great idea — let’s do more of that. Real calls mix the two languages, as in “payment कब तक हो जाएगा”, with the Hindi in Devanagari and the English in Roman. If you write the way people already talk, the agent sounds like one of them.The long version, with the structure, the number tables and the test loop, is the prompting guide.
After Tim Peters, The Zen of Python (PEP 20). Like Python’s list, this one
has nineteen lines and leaves a twentieth unwritten.