Response templates

Make the HTTP simulator's responses dynamic with values from the request, generated IDs and times, and fake names, emails and addresses.

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Response bodies and header values in the HTTP simulator can include templates: {{…}} placeholders replaced for each request. Use the Insert value menu above the body to add one at the cursor.

json
{
  "id": "{{path.id}}",
  "name": "{{fake.name}}",
  "email": "{{fake.email}}",
  "createdAt": "{{now}}"
}
The Insert value menu above a response body, with request values, generated values and Fake dataThe Insert value menu above a response body, with request values, generated values and Fake data
Insert value adds a template at the cursor.

Values from the request

Template Value
{{path.id}} The {id} segment of the route's path.
{{query.page}} A query-string parameter (the first, if repeated).
{{header.X-Tenant}} A request header; the name is case-insensitive.
{{body.user.name}} A JSON or form field by dot path. Numbers index arrays: {{body.items.0.id}}.

A value that isn't in the request is replaced by an empty string. So is a JSON object or array.

Generated values

Template Value
{{uuid}} A new random UUID.
{{now}} The current time in ISO 8601 UTC, such as 2026-10-14T08:53:20Z.
{{timestamp}} The current Unix time in seconds.

Fake data

A new value for every request:

Template Example
{{fake.firstName}}, {{fake.lastName}}, {{fake.name}} A first, last or full name
{{fake.email}} An email address on a safe example domain
{{fake.username}} A username
{{fake.phone}} A phone number
{{fake.company}}, {{fake.jobTitle}} A company name or job title
{{fake.street}}, {{fake.city}}, {{fake.state}}, {{fake.zip}}, {{fake.country}} Parts of an address
{{fake.word}}, {{fake.sentence}}, {{fake.paragraph}} Text
{{fake.ipv4}} An IPv4 address
{{fake.number}} A number from 0 to 999
{{fake.boolean}} true or false

Escaping and JSON

  • When a body starts with { or [, inserted values are escaped for JSON, so a quote in a request value can't break your JSON.
  • In header values, line breaks become spaces.
  • To send a literal {{, write \{{.

Templates are checked when you save the route. A typo such as {{fake.nme}}, an unclosed {{, or {{path.userId}} on a route without a {userId} segment is reported before it reaches your application.

Templates are values only: there are no conditions or calculations. To send different responses to different requests, use conditions.