# How to build a crypto trading bot in plain English, without it doing something stupid

*An AI agent does exactly what you write. Here is how to write it.*

Most trading bots fail before they place a trade, because the rules were never rules. "Buy when momentum looks strong" feels like a strategy. A machine can read it a dozen ways, and it will pick one you didn't mean.

I build Central Command, which has an agent builder that takes plain-English rules. This is what I would tell someone writing their first one. The examples use our builder, but the writing advice works in any tool that takes plain-language rules.

## Start with one sentence you could check by hand

Here is a complete strategy:

> Go long BTC when the hour closes above the 21 EMA with RSI over 50. Stop under the 10-hour low. Take profit at 2R. Risk 1% a trade.

Look at a chart and you could say yes or no to every part of that. That is the test. If you can't check a line by looking at a chart, the agent can't reliably follow it either.

Here is the same idea written badly:

> Buy BTC in an uptrend when RSI is healthy and manage risk sensibly.

"Uptrend", "healthy" and "sensibly" all leave the decision to the machine. You would get an agent that behaves, and you would have no idea why.

## Fill in the four boxes

Our builder has four boxes, and they are a good checklist whatever you use.

**1. When to enter.** Name the indicator, its settings, the number and the timeframe. "RSI(14) below 30 on the 1-hour close" is compiled into an exact check. "RSI is low" is not.

**2. How to manage the trade.** Say what happens after entry. Does the stop move to break-even at 1R? Does it trail? Do you take half off at the first target? If you write nothing, nothing happens.

**3. Stop loss and target.** Write where they go. An agent executes what you wrote, so if you write no stop, it trades without one. This is the most expensive thing to forget.

**4. Anything else.** Conditions that don't fit elsewhere go here: no new trades on Sundays, only one position per coin, skip when funding is above a level you name.

## Say "close" whenever you mean close

Price crossing a level mid-candle and a candle closing beyond it are two very different signals. Fast wicks trigger the first all day. If your idea depends on a confirmed move, write "when the 1-hour candle closes above". A strategy written around closes is judged on closed candles only.

## Pick the money settings on purpose

Below the rules you set:

- **Paper or Live.** Paper uses simulated money on live prices. Live places real orders on your BloFin account. Nothing is picked for you.
- **Budget and risk per trade.** Risk is the part that decides how long you survive a losing streak.
- **Max leverage and max open positions.** These are caps, so set them to what you would accept on your worst day.
- **How often it checks the market.** Match this to your timeframe. A 4-hour strategy doesn't need checking every minute.

Under More settings you can add a daily loss limit and a total loss stop. If you are running real money, those two are worth a minute of your time.

## Backtest, and read the part most people skip

A backtest replays your rules against closed BloFin candles with fees and funding included. Rules that can't be compiled are refused, with the reason, which is itself useful feedback on your writing.

The number to read first is the split. Results come back showing the first 70% of the period against the last 30%. If the strategy made its money in the first stretch and fell apart in the second, you probably fitted it to the past.

A good backtest is still only a good backtest. It is not a result.

## Then watch what it thinks

Every check an agent makes is written to a Thinking feed: the data it read, how it reasoned and what it decided. For your first few days, read it. You will almost always find a line where the agent took your words literally and you meant something else. Fix that sentence and it behaves differently at its next check.

## Don't want to start from a blank page?

The [strategy library](/go/blog-bot?to=/strategies/library) has ready-made strategies written as plain rules, from breakouts to mean reversion, that you can load into the builder and change.

If you would rather start with your own idea, [the builder is here](/go/blog-bot?to=/agents/new). It is free with a BloFin account, or there is a 10-day free trial with no card.

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*Disclosure: I build Central Command, which earns a commission from BloFin on members' trading. This article was drafted with AI assistance. It is not financial advice. Past results, paper or live, do not guarantee future returns, and leveraged trading can lose all of your money.*