diff --git a/packages/backend/src/server/ActivityPubServerService.ts b/packages/backend/src/server/ActivityPubServerService.ts
index 8fa8320c8c..24f33fd609 100644
--- a/packages/backend/src/server/ActivityPubServerService.ts
+++ b/packages/backend/src/server/ActivityPubServerService.ts
@@ -162,23 +162,25 @@ export class ActivityPubServerService {
 			return true;
 		}
 
+		const keyId = new URL(signature.keyId);
+		const keyHost = this.utilityService.toPuny(keyId.hostname);
+
+		const logPrefix = `${request.id} ${request.url} (by ${request.headers['user-agent']}) apparently from ${keyHost}:`;
+
 		if (signature.params.headers.indexOf('host') === -1
 			|| request.headers.host !== this.config.host) {
 			// no destination host, or not us: refuse
-			this.authlogger.warn(`${request.id} ${request.url} no destination host, or not us: refuse`);
+			this.authlogger.warn(`${logPrefix} no destination host, or not us: refuse`);
 			reply.code(401);
 			return true;
 		}
 
-		const keyId = new URL(signature.keyId);
-		const keyHost = this.utilityService.toPuny(keyId.hostname);
-
 		const meta = await this.metaService.fetch();
 		if (this.utilityService.isBlockedHost(meta.blockedHosts, keyHost)) {
 			/* blocked instance: refuse (we don't care if the signature is
 				 good, if they even pretend to be from a blocked instance,
 				 they're out) */
-			this.authlogger.warn(`${request.id} ${request.url} instance ${keyHost} is blocked: refuse`);
+			this.authlogger.warn(`${logPrefix} instance is blocked: refuse`);
 			reply.code(401);
 			return true;
 		}
@@ -193,13 +195,13 @@ export class ActivityPubServerService {
 			/* keyId is often in the shape `${user.uri}#${keyname}`, try
 				 fetching information about the remote user */
 			const candidate = formatURL(keyId, { fragment: false });
-			this.authlogger.info(`${request.id} ${request.url} we don't know the user for keyId ${keyId}, trying to fetch via ${candidate}`);
+			this.authlogger.info(`${logPrefix} we don't know the user for keyId ${keyId}, trying to fetch via ${candidate}`);
 			authUser = await this.apDbResolverService.getAuthUserFromApId(candidate);
 		}
 
 		if (authUser?.key == null) {
 			// we can't figure out who the signer is, or we can't get their key: refuse
-			this.authlogger.warn(`${request.id} ${request.url} we can't figure out who the signer is, or we can't get their key: refuse`);
+			this.authlogger.warn(`${logPrefix} we can't figure out who the signer is, or we can't get their key: refuse`);
 			reply.code(401);
 			return true;
 		}
@@ -207,20 +209,20 @@ export class ActivityPubServerService {
 		let httpSignatureValidated = httpSignature.verifySignature(signature, authUser.key.keyPem);
 
 		if (!httpSignatureValidated) {
-			this.authlogger.info(`${request.id} ${request.url} failed to validate signature, re-fetching the key for ${authUser.user.uri}`);
+			this.authlogger.info(`${logPrefix} failed to validate signature, re-fetching the key for ${authUser.user.uri}`);
 			// maybe they changed their key? refetch it
 			authUser.key = await this.apDbResolverService.refetchPublicKeyForApId(authUser.user);
 
 			if (authUser.key != null) {
 				httpSignatureValidated = httpSignature.verifySignature(signature, authUser.key.keyPem);
 			} else {
-				this.authlogger.warn(`${request.id} ${request.url} failed to re-fetch key for ${authUser.user}`);
+				this.authlogger.warn(`${logPrefix} failed to re-fetch key for ${authUser.user}`);
 			}
 		}
 
 		if (!httpSignatureValidated) {
 			// bad signature: refuse
-			this.authlogger.info(`${request.id} ${request.url} failed to validate signature: refuse`);
+			this.authlogger.info(`${logPrefix} failed to validate signature: refuse`);
 			reply.code(401);
 			return true;
 		}