Choose the scope
Header capture and attachment apply only to enabled profiles and configured target origins.
Chrome extension for API development
Relay the headers your browser workflow needs.
Header Relay captures selected response headers and attaches fixed or captured values to later requests for the origins you choose.
profile / local-api / enabled
Response from target origin
x-session-token: dev-session-42
Next matching request
x-client-id: header-relay
x-session-token: dev-session-42
x-session-token: dev-session-42
Enabled for this target origin
A controlled request flow.
Configure a target origin, choose the headers involved, and inspect the resulting session without changing your application code.
Capture a value
Selected response header values are kept in the extension's local session state.
Relay the header
Fixed and captured headers are attached to later matching requests. Excluded paths remain untouched.
Local by design.
The extension is intended for local, staging, internal, and test environments. Its data handling stays narrow and inspectable.
No external data service
Profiles, captured values, session state, and audit logs are not sent to the developer or an external server.
Clear retention limits
Audit logs keep up to 1,000 recent entries for no more than 7 days, and can be cleared at any time.
Reduced URL logging
Logged URLs contain only the origin and pathname. Query strings and fragments are omitted.
User-controlled scope
Disable a profile, remove target origins, clear captured values, or uninstall the extension to stop its behavior.
Header Relay requests broad host permission so you can select local, staging, internal, or test origins. Actual capture and attachment remain limited to the enabled profile's configured origins and exclusions.
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Header Relay questions, answered.
The essentials for evaluating how Header Relay fits an API development workflow.
What does Header Relay do?
Header Relay captures response headers you select and adds fixed or captured header values to later browser requests that match your enabled profile.
Which requests can Header Relay modify?
Only requests matching an enabled profile's configured target origins are eligible. Excluded paths remain untouched.
Does Header Relay send data to an external server?
No. Profiles, captured values, session state, and audit logs remain in the local Chrome profile unless you choose to export or disclose them.
Where should I use Header Relay?
Header Relay is designed for API development and testing in local, staging, internal, and other controlled environments.