I built ajax-hooker, a browser-side AJAX interceptor for runtime request/response control (debugging, userscripts, extension tooling, temporary API rewrites).

GitHub: https://github.com/Arktomson/ajaxInterceptor npm: https://www.npmjs.com/package/ajax-hooker

What it does:

One unified hook model for XMLHttpRequest + fetch Mutate request fields: URL / method / headers / body Observe or rewrite response payloads Chain multiple hooks (auth/logging/rewrite separated) Stream interception for SSE/NDJSON-like responses Typical use cases:

Add auth/tracing headers globally Switch API domain/version without touching app code Mock or patch responses during integration/debug Build userscript or Chrome-extension request tooling I’d really appreciate feedback on:

API ergonomics for hook composition edge cases around fetch response semantics stream interception behavior in real-world apps