// CATEGORY · knowledge/bugs/

Bug Stories

Post-mortems and fixes — what broke, what we assumed, and what actually worked.

1 published story

Dev story — work in progress

These posts are engineering notes from building Koko. They capture what we believed at the time — some lessons aged well, some did not. Treat them as a lab notebook, not official docs. Corrections and better ideas are welcome.

Other categories

All Bug Stories1 Captcha & Detection1 Performance1 SDK1 Browser Engine1

Bug Storiesbugs/2026-06-29-google-search-nid-trust-tier.md

Google Search Trust Tier Is Gated by Mature `NID` Cookie, Not Guest Cookies

Koko coldstart Google Search without cookies always receives the long path: 91 KB bootstrap HTML with , inline , and a clientside redirect to or . Injecting a session cookie exported from the user's real Chrome profile flips hop1 to the short path: 266–331 KB direct SERP HTML, no gate variables, n

June 29, 2026

8 min read

Read story