feat: add fuzz testing harnesses and fix crash in nostrEventSchemas

- Expand fuzzing coverage for `js/nostrEventSchemas.js` to include all builder functions.
- Fix a crash in `buildAdminListEvent` where non-array `hexPubkeys` caused a TypeError.
- Update `scripts/agent/fuzz-dmDecryptor.mjs` and `scripts/agent/fuzz-magnetUtils.mjs` iterations.
- Add reproducer for the `buildAdminListEvent` crash.
- Generate fuzz reports in `artifacts/`.

Co-authored-by: PR0M3TH3AN <[email protected]>

examples/reproducers/crash-buildAdminListEvent-hexPubkeys.json

@@ -0,0 +1,10 @@
+{
+  "target": "nostrEventSchemas",
+  "timestamp": "2026-01-28T16:18:44.207Z",
+  "error": {
+    "message": "hexPubkeys.forEach is not a function",
+    "stack": "TypeError: hexPubkeys.forEach is not a function\n    at Module.buildAdminListEvent (file:///app/js/nostrEventSchemas.js:2535:14)\n    at fuzzTest (file:///app/scripts/agent/fuzz-nostrEventSchemas.mjs:232:17)\n    at runFuzzer (file:///app/scripts/agent/fuzz-shared.mjs:164:21)",
+    "name": "TypeError"
+  },
+  "input": null
+}

js/nostrEventSchemas.js

@@ -2532,11 +2532,13 @@ export function buildAdminListEvent(listKey, params) {
     tags.push([schema.identifierTag.name, schema.identifierTag.value]);
   }
   const participantTagName = schema?.participantTagName || "p";
+  if (Array.isArray(hexPubkeys)) {
     hexPubkeys.forEach((hex) => {
       if (typeof hex === "string" && hex.trim()) {
         tags.push([participantTagName, hex.trim()]);
       }
     });
+  }
   appendSchemaTags(tags, schema);
 
   const event = {

scripts/agent/fuzz-dmDecryptor.mjs

@@ -69,7 +69,7 @@ async function fuzzTest(iteration) {
   return { event, context };
 }
 
-runFuzzer("dmDecryptor", 5000, fuzzTest)
+runFuzzer("dmDecryptor", 10000, fuzzTest)
   .catch(err => {
     console.error("Fatal fuzzer error:", err);
     process.exit(1);

scripts/agent/fuzz-magnetUtils.mjs

@@ -101,7 +101,7 @@ async function fuzzTest(iteration) {
   return { rawValue, options };
 }
 
-runFuzzer("magnetUtils", 5000, fuzzTest).catch(err => {
+runFuzzer("magnetUtils", 10000, fuzzTest).catch(err => {
     console.error("Fatal fuzzer error:", err);
     process.exit(1);
 });

scripts/agent/fuzz-nostrEventSchemas.mjs

@@ -25,7 +25,26 @@ async function fuzzTest(iteration) {
     "buildZapRequestEvent",
     "sanitizeAdditionalTags",
     "validateEventStructure",
-    "setNostrEventSchemaOverrides"
+    "setNostrEventSchemaOverrides",
+    "buildRepostEvent",
+    "buildShareEvent",
+    "buildRelayListEvent",
+    "buildDmRelayListEvent",
+    "buildProfileMetadataEvent",
+    "buildMuteListEvent",
+    "buildDeletionEvent",
+    "buildLegacyDirectMessageEvent",
+    "buildDmAttachmentEvent",
+    "buildDmReadReceiptEvent",
+    "buildDmTypingIndicatorEvent",
+    "buildWatchHistoryEvent",
+    "buildSubscriptionListEvent",
+    "buildBlockListEvent",
+    "buildHashtagPreferenceEvent",
+    "buildAdminListEvent",
+    "buildHttpAuthEvent",
+    "buildReportEvent",
+    "buildVideoMirrorEvent"
   ];
 
   const targetName = rng.oneOf(targets);
@@ -33,7 +52,7 @@ async function fuzzTest(iteration) {
 
   // Helper to generate a comprehensive random params object
   const genParams = () => {
-    // 50% chance of being undefined/null/non-object to test robustness
+    // 10% chance of being undefined/null/non-object to test robustness
     if (Math.random() < 0.1) return rng.nastyString();
     if (Math.random() < 0.1) return null;
 
@@ -52,15 +71,28 @@ async function fuzzTest(iteration) {
         "videoEventId", "videoEventRelay", "videoDefinitionAddress", "rootIdentifier",
         "parentCommentId", "rootKind", "rootAuthorPubkey", "parentKind",
         "recipientPubkey", "relays", "amountSats", "lnurl", "eventId", "coordinate",
-        "targetPointer", "targetAuthorPubkey"
+        "targetPointer", "targetAuthorPubkey",
+        // Added fields
+        "repostKind", "targetKind", "targetEvent", "serializedEvent",
+        "video", "metadata", "pTags", "encrypted", "encryptionTag",
+        "eventIds", "addresses", "reason", "ciphertext", "attachment",
+        "messageKind", "expiresAt", "monthIdentifier", "hexPubkeys",
+        "payload", "reportType", "address", "addressRelay", "authorPubkey",
+        "eventRelay", "method", "userId", "relayHint"
     ];
 
     extraFields.forEach(field => {
         if (rng.bool()) {
             params[field] = rng.mixedString(50);
         } else if (rng.bool()) {
+            if (field === "targetEvent" || field === "video" || field === "attachment" || field === "metadata") {
+                params[field] = rng.recursiveObject(2);
+            } else if (field === "relays" || field === "pTags" || field === "eventIds" || field === "addresses" || field === "hexPubkeys") {
+                params[field] = rng.array(() => rng.mixedString(64), 5);
+            } else {
                 params[field] = rng.recursiveObject(1); // Potentially invalid type
             }
+        }
     });
 
     return params;
@@ -132,12 +164,91 @@ async function fuzzTest(iteration) {
        // Trigger usage
        Schemas.getNostrEventSchema(randomType);
        break;
+
+    case "buildRepostEvent":
+        inputs = genParams();
+        Schemas.buildRepostEvent(inputs);
+        break;
+    case "buildShareEvent":
+        inputs = genParams();
+        Schemas.buildShareEvent(inputs);
+        break;
+    case "buildRelayListEvent":
+        inputs = genParams();
+        Schemas.buildRelayListEvent(inputs);
+        break;
+    case "buildDmRelayListEvent":
+        inputs = genParams();
+        Schemas.buildDmRelayListEvent(inputs);
+        break;
+    case "buildProfileMetadataEvent":
+        inputs = genParams();
+        Schemas.buildProfileMetadataEvent(inputs);
+        break;
+    case "buildMuteListEvent":
+        inputs = genParams();
+        Schemas.buildMuteListEvent(inputs);
+        break;
+    case "buildDeletionEvent":
+        inputs = genParams();
+        Schemas.buildDeletionEvent(inputs);
+        break;
+    case "buildLegacyDirectMessageEvent":
+        inputs = genParams();
+        Schemas.buildLegacyDirectMessageEvent(inputs);
+        break;
+    case "buildDmAttachmentEvent":
+        inputs = genParams();
+        Schemas.buildDmAttachmentEvent(inputs);
+        break;
+    case "buildDmReadReceiptEvent":
+        inputs = genParams();
+        Schemas.buildDmReadReceiptEvent(inputs);
+        break;
+    case "buildDmTypingIndicatorEvent":
+        inputs = genParams();
+        Schemas.buildDmTypingIndicatorEvent(inputs);
+        break;
+    case "buildWatchHistoryEvent":
+        inputs = genParams();
+        Schemas.buildWatchHistoryEvent(inputs);
+        break;
+    case "buildSubscriptionListEvent":
+        inputs = genParams();
+        Schemas.buildSubscriptionListEvent(inputs);
+        break;
+    case "buildBlockListEvent":
+        inputs = genParams();
+        Schemas.buildBlockListEvent(inputs);
+        break;
+    case "buildHashtagPreferenceEvent":
+        inputs = genParams();
+        Schemas.buildHashtagPreferenceEvent(inputs);
+        break;
+    case "buildAdminListEvent":
+        inputs = genParams();
+        // buildAdminListEvent(listKey, params)
+        const listKey = rng.oneOf(["moderation", "editors", "whitelist", "blacklist", "communityBlacklistSources", rng.nastyString()]);
+        Schemas.buildAdminListEvent(listKey, inputs);
+        break;
+    case "buildHttpAuthEvent":
+        inputs = genParams();
+        Schemas.buildHttpAuthEvent(inputs);
+        break;
+    case "buildReportEvent":
+        inputs = genParams();
+        Schemas.buildReportEvent(inputs);
+        break;
+    case "buildVideoMirrorEvent":
+        inputs = genParams();
+        Schemas.buildVideoMirrorEvent(inputs);
+        break;
   }
 
   return { target: targetName, inputs };
 }
 
-runFuzzer("nostrEventSchemas", 5000, fuzzTest).catch(err => {
+runFuzzer("nostrEventSchemas", 10000, fuzzTest).catch(err => {
     console.error("Fatal fuzzer error:", err);
     process.exit(1);
 });