feat(trust): confidence gate on the local ladder

A lone friend-of-a-friend no longer reads as trust. useViewerGraph now
counts distinct follows per friend-of-a-friend (fofCounts), and
deriveLocalScore returns verified only at FOF_MIN_RATERS (2) or more.
Provider assertions are unaffected; the full GrapeRank confidence model
stays provider-side. Docs updated.

AGENTS.md

@@ -2565,14 +2565,19 @@ kind-10040 provider designation** (`useSetTrustProvider`: custom npub/hex +
 `wss://` relay, or clear to fall back to the community provider). The local
 (non-provider) ladder is computed **once per viewer** by `useViewerGraph` and
 shared, so `TrustBadge` no longer fires a per-card `useTrustScore` graph query.
+The local ladder has a **confidence gate**: `useViewerGraph` counts distinct
+follows per friend-of-a-friend and `deriveLocalScore` only verifies at
+`FOF_MIN_RATERS` (2) or more, so a lone endorsement is not trust; provider
+assertions are unaffected.
 **Mute landed:** `useMuteList` + `useMuteUser` (NIP-51 kind-10000, optimistic via
 `lib/localMutes.ts`) feed `useAdminModeration`'s new `mutedPubkeys`, so the
 shared `filterAdminHidden` drops muted authors across every list; the flagged
 notice has a Mute action. **Alerts landed:** `useNetworkAlerts` + `/alerts`
 (`pages/NetworkAlertsPage.tsx`) list accounts you follow that trusted people
 reported/muted, with Ignore/Unfollow/Mute/Report; Settings → Trust links to it
-with a count (ignored set in `skatespots:trust:alerts-ignored`). Still open: the
-confidence-gated scoring model. Check
+with a count (ignored set in `skatespots:trust:alerts-ignored`). Still open:
+running our own GrapeRank-style scorer in `cvm-server` — the full confidence
+model is provider-side today. Check
 `TRUST_SCORE.md` before touching `useTrustScore` / `useRelatrScore` /
 `trustFilter`.
 

TRUST_SCORE.md

@@ -84,7 +84,16 @@ flagged notice's reporter breakdown, and Settings → Trust.
   `useMuteUser`, `ReportDialog`) — inform, never auto-act.
 - Settings → Trust links to it with a live count.
 
-Still open: the confidence-gated scoring model.
+## Sixth pass — local confidence gate (landed)
+
+- The fallback local ladder now gates a friend-of-a-friend behind a confidence
+  threshold: `useViewerGraph` counts distinct follows per friend-of-a-friend, and
+  `deriveLocalScore` returns `verified` only at `FOF_MIN_RATERS` (2) or more. A
+  lone endorsement no longer reads as trust.
+- Provider assertions are unaffected: the full GrapeRank confidence model lives
+  in the provider and we consume it via NIP-85. Running our own scorer (planned
+  for `cvm-server`, publishing kind-30382) remains the open item — it is the only
+  way to get the real confidence gate and a server-published score.
 
 
 

src/hooks/useViewerGraph.ts

@@ -9,11 +9,14 @@ const HOUSE_GRAPH_PUBKEY = '20e7c953439e66f3882ab96fe0faa8ba246d6fb12c03b0cb4e2d
 
 const MAX_FOLLOWS = 100;
 
+/** Distinct follows that must agree before a friend-of-a-friend counts as a vouch. */
+const FOF_MIN_RATERS = 2;
+
 export interface ViewerGraph {
   /** Pubkeys the graph owner follows. */
   following: Set<string>;
-  /** Friends-of-friends: pubkeys followed by someone the owner follows. */
-  fof: Set<string>;
+  /** Friends-of-friends, keyed by how many of the owner's follows follow them. */
+  fofCounts: Map<string, number>;
 }
 
 /**
@@ -44,28 +47,33 @@ export function useViewerGraph() {
         if (tag[0] === 'p' && tag[1]) following.add(tag[1]);
       }
 
-      const fof = new Set<string>();
+      const fofCounts = new Map<string, number>();
       if (following.size > 0) {
         const fofEvents = onlyVerified(await nostr.query(
           [{ kinds: [3], authors: [...following].slice(0, MAX_FOLLOWS), limit: MAX_FOLLOWS }],
           { signal },
         ));
         for (const event of fofEvents) {
+          // Count DISTINCT raters: guard against a malformed list repeating a p tag.
+          const seen = new Set<string>();
           for (const [name, value] of event.tags) {
-            if (name === 'p' && value) fof.add(value);
+            if (name !== 'p' || !value || seen.has(value)) continue;
+            seen.add(value);
+            fofCounts.set(value, (fofCounts.get(value) ?? 0) + 1);
           }
         }
       }
 
-      return { following, fof };
+      return { following, fofCounts };
     },
   });
 }
 
 /**
- * The same 100 / 90 / 60 / 0 ladder the trust badges used, minus the NIP-05 tier
- * (30) which classified as `unknown` anyway. `self` is the real viewer only —
- * never the house graph owner.
+ * The 100 / 90 / 60 / 0 ladder the trust badges used, minus the NIP-05 tier
+ * (30) which classified as `unknown` anyway, and with a confidence gate: a
+ * friend-of-a-friend counts only when at least `FOF_MIN_RATERS` distinct follows
+ * agree. `self` is the real viewer only — never the house graph owner.
  */
 export function deriveLocalScore(
   graph: ViewerGraph | undefined,
@@ -76,6 +84,8 @@ export function deriveLocalScore(
   if (viewer && pubkey === viewer) return 100;
   if (!graph) return undefined;
   if (graph.following.has(pubkey)) return 90;
-  if (graph.fof.has(pubkey)) return 60;
+  // Confidence gate: a single friend-of-a-friend is not a network vouch. Require
+  // at least FOF_MIN_RATERS distinct follows to agree before calling it verified.
+  if ((graph.fofCounts.get(pubkey) ?? 0) >= FOF_MIN_RATERS) return 60;
   return 0;
 }