docs: correct claims the code does not support

CLAUDE.md

@@ -26,15 +26,17 @@ than none. Whoever asked you to make this change will tell you your scope.
 
 ## `TODO(name), Day n:` markers are assignments
 
-There are none left — every stub from the original build has been implemented. The convention is
+One stub is left, and it still carries its marker. `registerDynamicTool` in
+`traces/src/lib/webmcp/register-tools.ts:133` throws `registerDynamicTool: not implemented`, and nothing
+in the codebase calls it — so promoting a hypothesis does not grow a 17th tool. The convention is
 documented here because the rule outlives the markers: a marker names the person who owned the work and
 the day it was due, so **deleting one while implementing around it destroys the only record of who owes
 what.** If you add a marker, name yourself in it. If you find one, either implement it or leave it
 exactly where it is.
 
 ## The tests are green, and two suites must stay honest
 
-All 285 tests pass. That is worth stating because of how some of them got there: the `compress-dom`,
+All 303 tests pass. That is worth stating because of how some of them got there: the `compress-dom`,
 `bisect` and `evaluatePredicate` suites were written first, as specifications, and were red for as long
 as it took the implementations to satisfy them. **Never** make a test in those suites pass by weakening
 an assertion, adding `.skip`, or deleting a case: that converts a specification into a lie, silently. A

traces/src/components/ui/tool-status-banner.tsx

@@ -136,8 +136,9 @@ export function ToolStatusBanner({ registration }: ToolStatusBannerProps) {
   }, [])
 
   /**
-   * `toolchange` is how a surface that grew a tool mid-investigation shows up here without a reload —
-   * the promoted-hypothesis tool from `registerDynamicTool` is the case worth demoing. The event fires
+   * `toolchange` is how a surface that grew a tool mid-investigation would show up here without a reload.
+   * Nothing in this app grows one: `registerDynamicTool` is a stub that throws and has no callers, so the
+   * only thing that can move this counter is the host changing its own tool list. The event fires
    * on `document.modelContext`, which is why the draft has it extend `EventTarget`. Not every host
    * honours that, and one of them is ChatGPT Desktop; `onToolChange` explains what subscribing there
    * used to cost. When the host has no events this counter simply never moves.