spike

# `spike` — measure the blackbox before you describe it gflow-cli drives a product it does not own. Every statement about what Flow does is either **measured** or **guessed**, and a guess written into code or docs becomes a fact nobody re-checks. **Load this skill before you write, say, or encode any of these:** - "X is not supported / not available / not rendered on this host" - "this surface is labs-only" · "the migrated host cannot do X" - "the selector is gone" · "Flow removed it" - a `raise_if_migrated`-style guard, a capability table, or a KNOWN_ISSUES entry asserting an absence - an issue reply telling a user a feature cannot work ## The rule this exists to enforce ``` A SELECTOR THAT DOES NOT MATCH IS EVIDENCE ABOUT THE SELECTOR. IT IS NEVER EVIDENCE ABOUT THE FEATURE. ``` A wait that times out tells you your anchor missed. It tells you nothing about whether the thing exists. To claim absence you need a **positive observation of absence** — a DOM inventory that lists what IS there, a network log that shows what was and was not called. "It timed out" is not that. > **Written from a two-line failure that cost a day.** On 2026-09-06 `gflow character > create` was believed impossible on `flow.google.com`. The entire chain came from one > 20 s readiness timeout: selector missed → gate timed out → "no prompt textbox" → > "labs-only surface" → "renders no prompt textbox for it, **ever**", shipped in a code > comment, the CHANGELOG, a release ledger and a test class ...