> For the complete documentation index, see [llms.txt](https://docs-en.yoctol.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs-en.yoctol.ai/chatbot-building-guide/7-set-rules.md).

# (7) Set Rules

### Things you should know

Rules are a set of certain conditions to tell the bot what to respond. To put it simply, rules are the connections between **“what bot understands”** (e.g., NLU) and **”what bot responds”** (e.g., message). Setting rules means to set up which message the bot will respond with, once the bot understands certain contents.

### Steps

1. Click on **`My Bot`** > **`Dialogue`**
2. Select the **message** that you want to add rules on.
3. On the top, select **`Rules`** , then add a rule by clicking **`+ Rule`**
4. On **`Type`** , choose the type of rule (Types are illustrated as follow.)

![](/files/-LpSH_sqCyWXYiI5qaj-)

### Types of Rules

1. NLU (Intent and Entity)
2. Keyword matching (one or more keywords)
3. Regular expression

Method 1 and 2 are more commonly used. Below is an in-depth description on the differences.

#### 1. Using NLU as a rule

‌Set a rule with intents and/ or entity as a rule. 

For example: Intent **“Take away”**, **“Price”**, Entity **“Drinks”**

![](/files/-LpSHdDlA4ci21iZ7bFm)

![](/files/-LpSHgA795SCPvcPTUgD)

#### 2. Using keyword matching as a rule

For instance, you can set keywords such as “take away” or “order” as a rule. When any of these keywords appears in the sentence, it tells the bot to respond with this message.

![](/files/-LpSHiu77Kggful1jVUh)

#### ‌3. Using regular expressions as a rule

Regular expression is a sequence of characters that define a search pattern. \
For instance, you want to set up a rule that can match the words including “order” and “take away”, you can use regular expression as the rule. 

**I want to order drinks.**\
**I want to take away .**

The above sentences, you can use a single regular expression to match both of them.

**^I (want|would like to) (order|take away)(drinks)?.$**

For more detailed tutorial, check out [Regular Expression](https://app.gitbook.com/@docs-en-yoctol-ai/s/yoctol/~/edit/drafts/-LnQJsTXatUDJ-slOjKr/v/master/term-translations/regular-expression)

![](/files/-LpSHlyBs_M9YNnuQUhN)

{% hint style="danger" %}
Note: A particular rule can be only used in one message. A message can contain several rules.
{% endhint %}

##