diff --git a/sdks/agent-sdk/src/user/NameResolver.ts b/sdks/agent-sdk/src/user/NameResolver.ts
index 13dda626f..4cb32af0a 100644
--- a/sdks/agent-sdk/src/user/NameResolver.ts
+++ b/sdks/agent-sdk/src/user/NameResolver.ts
@@ -1,4 +1,5 @@
 import { escape } from "node:querystring";
+import { IdentifierKind, type GroupMember } from "@xmtp/node-sdk";
 import { isAddress } from "viem";
 import { AgentError } from "@/core/AgentError.js";
 import { LimitedMap } from "@/utils/LimitedMap.js";
@@ -62,3 +63,236 @@ const resolveName = async (
 export const createNameResolver = (apiKey?: string) => {
   return (name: string) => resolveName(name, apiKey);
 };
+
+/**
+ * Matches a shortened address against a list of full addresses
+ * @param shortenedAddress - Shortened address like "0xabc5…f002"
+ * @param fullAddresses - Array of full Ethereum addresses to match against
+ * @returns Matched full address or null if no match found
+ */
+export const matchShortenedAddress = (
+  shortenedAddress: string,
+  fullAddresses: string[],
+): string | null => {
+  const match = shortenedAddress.match(
+    /^(0x[a-fA-F0-9]+)(?:…|\.{2,3})([a-fA-F0-9]+)$/,
+  );
+  if (!match) return null;
+
+  const [, prefix, suffix] = match;
+  if (!prefix || !suffix) return null;
+
+  for (const fullAddress of fullAddresses) {
+    const normalized = fullAddress.toLowerCase();
+    if (
+      normalized.startsWith(prefix.toLowerCase()) &&
+      normalized.endsWith(suffix.toLowerCase())
+    ) {
+      return fullAddress;
+    }
+  }
+
+  return null;
+};
+
+/**
+ * Extracts Ethereum addresses from group members
+ * @param members - Array of group members
+ * @returns Array of Ethereum addresses
+ */
+export const extractMemberAddresses = (members: GroupMember[]): string[] => {
+  const addresses: string[] = [];
+  for (const member of members) {
+    const ethIdentifier = member.accountIdentifiers.find(
+      (id) => id.identifierKind === IdentifierKind.Ethereum,
+    );
+    if (ethIdentifier) {
+      addresses.push(ethIdentifier.identifier);
+    }
+  }
+  return addresses;
+};
+
+/**
+ * Resolves an identifier to an Ethereum address
+ * Handles full addresses, shortened addresses (in groups), and domain names
+ * @param identifier - Ethereum address or domain name to resolve
+ * @param memberAddresses - Optional array of member addresses to match shortened addresses against
+ * @param resolveAddress - Function to resolve domain names to addresses
+ * @returns Ethereum address or null if not found
+ */
+export const resolveIdentifier = async (
+  identifier: string,
+  memberAddresses?: string[],
+  resolveAddress?: (name: string) => Promise<string | null>,
+): Promise<string | null> => {
+  if (identifier.match(/^0x[a-fA-F0-9]{40}$/)) {
+    return identifier;
+  }
+
+  if (identifier.match(/0x[a-fA-F0-9]+(?:…|\.{2,3})[a-fA-F0-9]+/)) {
+    return memberAddresses?.length
+      ? matchShortenedAddress(identifier, memberAddresses)
+      : null;
+  }
+
+  const nameToResolve = identifier.includes(".")
+    ? identifier
+    : `${identifier}.farcaster.eth`;
+
+  if (!resolveAddress) return null;
+
+  try {
+    return await resolveAddress(nameToResolve);
+  } catch {
+    return null;
+  }
+};
+
+/**
+ * Extracts mentions/domains from a message
+ * Supports formats: @domain.eth, @username, domain.eth, @0xabc...def, @0xabcdef123456
+ * @param message - The message text to parse
+ * @returns Array of extracted identifiers
+ */
+export const extractMentions = (message: string): string[] => {
+  const mentions: string[] = [];
+
+  const fullAddresses = message.match(/(0x[a-fA-F0-9]{40})\b/g);
+  if (fullAddresses) mentions.push(...fullAddresses);
+
+  const shortenedAddresses = message.match(
+    /@(0x[a-fA-F0-9]+(?:…|\.{2,3})[a-fA-F0-9]+)/g,
+  );
+  if (shortenedAddresses) {
+    mentions.push(...shortenedAddresses.map((m) => m.slice(1)));
+  }
+
+  const atMentions = message.match(/@(?!0x)([\w.-]+\.eth|[\w.-]+)/g);
+  if (atMentions) mentions.push(...atMentions.map((m) => m.slice(1)));
+
+  const domains = message.match(/\b(?<!@)([\w-]+(?:\.[\w-]+)*\.eth)\b/g);
+  if (domains) mentions.push(...domains);
+
+  const uniqueMentions = [...new Set(mentions)];
+
+  return uniqueMentions.filter((mention) => {
+    return !uniqueMentions.some(
+      (other) => other !== mention && other.endsWith(`.${mention}`),
+    );
+  });
+};
+
+/**
+ * Resolves all mentions in a message to Ethereum addresses
+ * @param message - The message text to parse
+ * @param members - Optional array of group members to match shortened addresses against
+ * @param resolveAddress - Function to resolve domain names to addresses
+ * @returns Object mapping identifiers to addresses
+ */
+export const resolveMentionsInMessage = async (
+  message: string,
+  members?: GroupMember[],
+  resolveAddress?: (name: string) => Promise<string | null>,
+): Promise<Record<string, string | null>> => {
+  const mentions = extractMentions(message);
+  if (mentions.length === 0) return {};
+
+  const memberAddresses = members ? extractMemberAddresses(members) : [];
+  const results: Record<string, string | null> = {};
+
+  await Promise.all(
+    mentions.map(async (mention) => {
+      results[mention] = await resolveIdentifier(
+        mention,
+        memberAddresses,
+        resolveAddress,
+      );
+    }),
+  );
+
+  return results;
+};
+
+/**
+ * Fetches Farcaster profile information from web3.bio
+ * @param name - Name or identifier to look up
+ * @param apiKey - Optional API key for web3.bio
+ * @returns Profile information including address, display name, platform, username, fid, and social stats
+ */
+const emptyProfile = {
+  address: null,
+  displayName: null,
+  platform: "",
+  username: null,
+  fid: null,
+  social: null,
+};
+
+export const fetchFarcasterProfile = async (
+  name: string,
+  apiKey?: string,
+): Promise<{
+  address: string | null | undefined;
+  displayName?: string | null;
+  platform: string;
+  username: string | null | undefined;
+  fid: string | null | undefined;
+  social?: {
+    uid: number | null;
+    follower: number | null;
+    following: number | null;
+  } | null;
+}> => {
+  try {
+    const endpoint = `https://api.web3.bio/profile/${escape(name)}`;
+    const headers: Record<string, string> = {
+      "Content-Type": "application/json",
+    };
+
+    if (apiKey) {
+      headers["X-API-KEY"] = `Bearer ${apiKey}`;
+    }
+
+    const response = await fetch(endpoint, {
+      method: "GET",
+      headers,
+    });
+
+    if (!response.ok) {
+      return emptyProfile;
+    }
+
+    const data = (await response.json()) as Array<{
+      address: string | null;
+      platform: string;
+      displayName?: string;
+      username?: string;
+      fid?: string;
+      social?: {
+        uid: number | null;
+        follower: number | null;
+        following: number | null;
+      };
+    }> | null;
+
+    const farcasterProfile = data?.find(
+      (profile) => profile.platform === "farcaster",
+    );
+
+    if (farcasterProfile) {
+      return {
+        address: farcasterProfile.address,
+        displayName: farcasterProfile.displayName,
+        platform: farcasterProfile.platform,
+        username: farcasterProfile.displayName || null,
+        fid: farcasterProfile.social?.uid?.toString() || null,
+        social: farcasterProfile.social || null,
+      };
+    }
+
+    return emptyProfile;
+  } catch {
+    return emptyProfile;
+  }
+};