Reading the code you live in

You already had the instinct right: .mjs is a recipe that does something, .json is where facts are stored. Today we sharpen that into the ability to open one of your own files and name every part.

One win: by the end you can point at a line in apply-prompts.mjs and say "that's a comment / a jar / a borrowed tool." · Cheat sheet: Glossary

01The kitchen

The whole repo is a kitchen. Five words unlock 90% of it. Learn these as a picture, not a definition:

The picture

.json = the order ticket. Just facts written down. "Table 4, Thai agent, ID 8425e11b." It doesn't do anything.

.mjs = the recipe. Steps that DO something. Your instinct — "a verb" — is exactly right.

node = the cook. The only one who can actually follow a .mjs recipe.

bash (the terminal) = you calling the order to the cook: node apply-prompts.mjs.

const = a labelled jar. Fill it once, reuse the label.

So when you run node apply-prompts.mjs production, you (in the terminal) are telling the cook (node) to follow the recipe (the .mjs) for the production shop. That's the whole sentence.

02Your real recipe, line by line

This is the actual top of vapi-pilot-phuket/apply-prompts.mjs — the script you run to push prompts to VAPI. Red italics are my notes, not part of the file:

apply-prompts.mjs

// SOURCE OF TRUTH for the booking-agent system prompts.   ← margin note. node ignores it. it's telling YOU why this file exists
// Edit the prompt? Edit the .md file, then run this.

import { readFileSync } from "node:fs";   ← borrow the "read a file" tool from Node's file kit
import { dirname } from "node:path";

const __dir = dirname(fileURLToPath(import.meta.url));  ← a jar labelled __dir = "the folder this script lives in"
const env = {};                              ← an empty jar we'll fill with the secret keys

for (const line of readFileSync(`${__dir}/../../../.env`, "utf8").split("\n")) {  ← for EACH line of the .env file…
  // …pull the KEY=VALUE out of the line and drop it in the env jar
}

Read it out loud in kitchen words: "Borrow the read-file tool. Make a jar called env. For each line of the secrets file, put the key into the jar." That's it. You don't need to write this — you need to recognise the shapes.

The one thing that trips beginners

Running the recipe and reading the recipe are different acts. node apply-prompts.mjs in the terminal = cook it now. Opening the file in an editor = read the recipe card. Same file, two different verbs. Reading never changes anything or costs anything — open your files freely.

03Your real order ticket

Now a .json — the top of MANIFEST-testing.json. Notice: no verbs, no actions. Just key : value pairs — a label and the fact behind it.

Key (the label)	Value (the fact)	In plain English
"relay_mode"	"REAL"	This account talks to the live GHL, not the stub.
"squad"	"1d9f570a-…"	The ID of the whole agent squad (router + languages).
"assistants"	{ … }	A ticket inside the ticket — nesting. Curly braces `{ }` group related facts.
"thai_booking_pt"	"8425e11b-…"	The exact ID of your Thai booking agent. This is the value you'd copy when a script asks "which agent?"

So JSON is two symbols, over and over: { } groups things, "key": value states a fact. That's the entire language. Your instinct — "where info is stored so a script can use it" — was dead on.

Safe to edit vs. easy to break

Safe: changing a value — e.g. "relay_mode": "REAL" → "STUB". You're changing a fact.

Breaks the file: deleting a comma, a quote, or a }. JSON is strict punctuation — one missing comma and the cook can't read the ticket at all (it "won't parse"). So: edit values, never touch the punctuation scaffolding. When unsure, ask me to check it before you save.

03Check yourself

No peeking at the glossary. Click to reveal after you've answered in your head.

1. In node apply-prompts.mjs, which word is the cook and which is the recipe?

reveal

node is the cook; apply-prompts.mjs is the recipe. You (in the terminal) called the order.

2. You see const key = "abc123". What is const doing?

reveal

Filling a labelled jar once. From now on key means "abc123", and it won't be re-pointed to a different value later.

3. One file only stores facts, no actions. Is it the .mjs or the .json?

reveal

The .json — the order ticket. The .mjs is the recipe that does things.

4. Your VAPI Thai agent stops working and you open MANIFEST-testing.json. Which part tells you its ID — a key or a value?

reveal

The value. "thai_booking_pt" is the label (key); "8425e11b-…" is the fact you're after (value).

04Do this once (2 minutes)

Skills stick by touching the real thing. In your terminal:

Type cd clients/duckycutz/run/vapi-pilot-phuket then open apply-prompts.mjs (or open it in your editor).
Find one comment, one const, and one import. Say each one's kitchen role out loud.
Now open MANIFEST-testing.json and read one "key": "value" pair out loud as a fact.

That's the win. You just read your own production code. Nothing exploded — because reading is free.

I'm your teacher — ask me anything. Point at any line in any of your files and say "what's this?" and I'll decode it against the kitchen. Unfamiliar word? I'll add it to your glossary.

Reading the code you live in

01The kitchen

02Your real recipe, line by line

03Your real order ticket

03Check yourself

04Do this once (2 minutes)

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