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A Power HTTP Interceptor to Intercept, Record, Debug & Modify HTTP Requests

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HTTP Headers

Tk

HTTP Header

Deprecated: This feature is no longer recommended. Although some browsers might still support it, it may have already been removed from current web standards, is in the process of being phased out, or is maintained solely for backward compatibility. Avoid using this feature and update existing code when possible. Refer to the compatibility table at the bottom of this page for guidance. Be aware that this feature could cease to function at any time.

Non-standard: This feature does not conform to standard specifications and is not part of any standards track. Do not use it on production websites accessible to the public, as it might not work for all users. There could also be significant incompatibilities between different implementations, and its behavior may change in the future.

Note:
The Do Not Track (DNT) specification has been discontinued. For more information, see Navigator.doNotTrack. As an alternative, there is Global Privacy Control, which is communicated to servers via the Sec-GPC header, and can be accessed by clients from navigator.globalPrivacyControl.The HTTP Tk response header indicates the tracking status applicable to the corresponding request.

Header typeResponse header
Forbidden request headerNo

Syntax

Tk: ! (under construction)
Tk: ? (dynamic)
Tk: G (gateway or multiple parties)
Tk: N (not tracking)
Tk: T (tracking)
Tk: C (tracking with consent)
Tk: P (potential consent)
Tk: D (disregarding DNT)
Tk: U (updated)

Directives

Under construction. The origin server is currently testing its communication of
tracking status.

These directives are used to communicate the tracking status between a user’s browser and the server, often in relation to privacy preferences and consent. Understanding these directives helps improve privacy management and compliance with regulations.

Note: The HTML below has been simplified, with all anchor tags replaced by paragraph tags and attributes removed for clarity.

Under construction. The origin server is currently testing its communication of tracking status.

The directives include:

!
Indicates that the system is still under development, and the communication of tracking status is being tested.
?
This indicates a dynamic situation where the server requires more information to determine tracking status.
G
The server is functioning as a gateway involving multiple parties, such as an exchange or partnership.
N
No tracking is being performed.
T
Tracking is active.
C
Tracking with user consent. The server believes it has received prior consent to track the user, user agent, or device.
P
Potential consent. The server is unsure if it has received consent in real-time but promises not to use or share DNT:1 data until confirmation is received. It also promises to delete or de-identify such data within 48 hours if consent is not granted.
D
The server disregards the Do Not Track (DNT) signal, indicating unwillingness or inability to respect tracking preferences.
U
The tracking status has been updated, indicating a potential change in tracking permissions for the user, user agent, or device.

How to Modify Header using Requestly

Requestly is a powerful Chrome extension that allows you to modify HTTP headers, including the Accept header. This is especially useful for testing how your application responds to different media types during development or debugging. Steps to Modify the Accept Header:

  1. Install and open the Requestly Chrome extension. You can find it on the Chrome Web Store.
  2. Create a new rule: Click on “Create Rule” and choose “Modify Headers” from the list of available rule types.
  3. Add a new header modification:
    • Under “Action”, select “Add” or “Override”.
    • In the “Header Name” field, enter Accept.
    • In the “Header Value” field, enter your preferred media type (e.g., text/html).
  4. Set the URL condition: Specify the URL or pattern where this header change should apply (e.g., https://your-api.com/*).
  5. Save the rule.

Once set up, Requestly will inject the Accept: text/html header into all matching requests, allowing you to simulate different client behaviors and test content negotiation on your server. You might need to modify the Accept header to see how your website or API responds to various formats like JSON, HTML, or XML. This helps in making sure your application works well with different types of clients and handles data in the best way possible.