fix(ai): strip an ID-selector prefix before the grounding lookup

packages/outpost/ai/src/groundedness.test.ts

@@ -103,6 +103,27 @@ describe('extractCopilotKitIdentifiers', () => {
         ).toEqual(['copilot-chat', 'copilotSidebarPanel']);
     });
 
+    // #234. The class-selector case above passed only because `split('.')` happened
+    // to strip the prefix; `#` had no such path, so an ID selector reached the
+    // grounding lookup with its prefix attached. Grounding is a substring check,
+    // so `#copilotkitpanel` could never match a source writing `copilotKitPanel` —
+    // the one spelling the docs actually use.
+    it('strips a leading ID-selector prefix from a backticked name', () => {
+        expect(extractCopilotKitIdentifiers('Target `#copilotKitPanel` to move it.')).toEqual([
+            'copilotKitPanel',
+        ]);
+    });
+
+    it('treats the ID and class spellings of one name as the same identifier', () => {
+        // Both forms case-fold to one key, so a single name cannot fill two of the
+        // two threshold slots on its own.
+        expect(
+            extractCopilotKitIdentifiers(
+                'Give the node `#copilotKitPanel` and style `.copilotKitPanel`.',
+            ),
+        ).toEqual(['copilotKitPanel']);
+    });
+
     it('unwraps a JSX component that carries props', () => {
         // A model writing a fabricated component almost always gives it props, so
         // the prop-less-only form was the least likely spelling to appear.
@@ -248,6 +269,18 @@ describe('extractCopilotKitIdentifiers', () => {
 });
 
 describe('assessGroundedness', () => {
+    // #234, the consequence that matters: two ID selectors the sources DO contain
+    // suppressed a correct answer outright, with nothing logged.
+    it('does not suppress ID-selector names the sources actually contain', () => {
+        const result = assessGroundedness(
+            'Target `#copilotKitPanel` and `#copilotKitSidebar` to reposition it.',
+            [source('Set copilotKitPanel and copilotKitSidebar on the wrapper nodes.')],
+        );
+        expect(result.unsourcedIdentifiers).toEqual([]);
+        expect(result.suppress).toBe(false);
+        expect(result.penalty).toBe(0);
+    });
+
     it('gives a grounded answer no penalty and does not suppress it', () => {
         const response =
             'You can replace the chat input with the `input` prop on the `CopilotChat` component. ' +

packages/outpost/ai/src/groundedness.ts

@@ -367,7 +367,25 @@ function identifierSegments(rawToken: string): string[] {
 
     // A dotted form names a member; report the segments that carry our name so the
     // grounding lookup compares something a source could plausibly contain.
-    return token.split('.').filter((segment) => segment && isCopilotKitIdentifier(segment));
+    //
+    // Splitting on `#` as well as `.` is what strips a selector prefix before the
+    // lookup. `IDENTIFIER_PATH` admits either prefix, but only `.` used to be
+    // split, so an ID selector reached grounding as `#copilotKitPanel` — and
+    // grounding is a substring check, so it could never match a source writing the
+    // bare `copilotKitPanel`, which is how the docs write it. Two such names then
+    // met SUPPRESS_AT_UNSOURCED_IDENTIFIERS and withheld a correct answer.
+    //
+    // This closes the false-SUPPRESSION half only. The two prefixes still reach
+    // this function by different routes: `CSS_CLASS_PATTERN` finds a class
+    // selector anywhere in the response, deliberately including inside a ```css
+    // fence, while an ID selector arrives only via `BACKTICKED_PATTERN`, which
+    // cannot span a newline and so never matches inside a fence. So a fabricated
+    // `#copilotKitFake` in a css fence is still invisible where `.copilotKitFake`
+    // is caught. Fixing that means widening `CSS_CLASS_PATTERN` to `[.#]`, which
+    // ADDS suppression — the direction that withholds correct answers — and `#`
+    // carries traps `.` does not (`this.#copilotFoo` passes the lookbehind, since
+    // the character before `#` is `.`). That belongs in its own change.
+    return token.split(/[.#]/).filter((segment) => segment && isCopilotKitIdentifier(segment));
 }
 
 /**