Variables Reference

Catalyst substitutes variables in any string using {{name}}. Environment variables use ${{NAME}}.

Sources

• CLI: --var key=value,token=$TOKEN
• Stored values: store = { "$.path" = "var" }
• Cookies: get_cookie = { "cookieName" = "var" }
• Environment: ${{ENV_NAME}} in strings
• Automatic:
  • response_time_ms: set after each test
  • header_<name>: response headers (lowercased), e.g. {{header_content-type}}

Usage

endpoint = "/users/{{user_id}}"
headers = { "Authorization" = "Bearer {{token}}" }
body = { "content" = "{{file:data/payload.txt}}" }

Type Inference

When a placeholder is the entire JSON value, Catalyst inspects the resolved text and automatically parses native types:

body = { user_ids = ["{{admin_user_id}}"], active = "{{is_active}}" }

If admin_user_id = "42" and is_active = "false", the request body becomes:

{ "user_ids": [42], "active": false }

Lists, objects, numbers, booleans, and null all round-trip as long as the stored value is valid JSON.

Explicit Casts

Add a suffix with |<type> to force a specific conversion. Casts work for both CLI variables and environment variables.

body = {
  user_ids = ["{{admin_user_id|int}}"],
  flags = "{{feature_flags|json}}",
  comment = "Mention {{admin_user_id|string}} user"
}

Supported casts:

• |int, |integer
• |float, |double, |number
• |bool, |boolean
• |string, |str
• |json (parses any JSON value)
• |array, |list
• |object, |map
• |null

If parsing fails, Catalyst falls back to the interpolated string so tests keep running.