Params and headers

Query parameters, path variables, and request headers — and how the key-value editor works.

In this chapter

• Query params
• Path variables
• Headers
• The key-value editor

Query params

The Params tab holds the request’s query string. Its rows stay in sync with the ?key=value pairs in the URL — edit either and the other updates. Each row has an enable checkbox, a Parameter (key) field, a Value field, a Description field (unique to params), and a delete button. Keys and values support {{variables}}, shown as accent pills.

Path variables

When your URL contains a :name segment — for example https://api.example.com/users/:id — a Path Variables section appears in the Params tab. Beacon detects each :name token (only after a /, so schemes and host:port are never mistaken for path variables) and lists it with an editable value field. These rows are derived from the URL, so they have no enable checkbox and no delete button.

At send time, each :name is replaced with its URL-encoded value. Values themselves are interpolated, so {{variables}} work here too.

Note: If you leave a path variable’s value empty, Beacon sends the literal :name in the URL rather than guessing. This is a deliberate loud failure — a broken-looking URL tells you at a glance that a value is missing.

Headers

The Headers tab is a key-value editor with an enable checkbox, a Header (key) field, a Value field, and a delete button. Keys and values support {{variables}}.

Clearing a row’s checkbox keeps the header in the list but omits it from the request — the row dims to show it won’t be sent. This lets you toggle a header off without losing it.

Note: Beacon adds some headers automatically at send time and does not show them in this list: Content-Type (derived from the body type) and Authorization (derived from the Authorization tab). Setting your own header of the same name overrides the automatic one.

The key-value editor

The Params, Headers, form-data, and urlencoded panels all use the same key-value editor:

• A header row of column labels appears once at least one row exists.
• Each row highlights on hover; disabled rows are dimmed.
• The + Add button at the bottom adds a blank row.
• The delete (trash) button removes a row and turns red on hover.

Note: These panels edit one row at a time. There is no bulk / raw-text edit mode in the request panels — that lives only in the collection-wide Find & Replace tool.

---

See also: Request body · Authorization · Variables and environments