diff --git a/packages/dvmcp-discovery/src/discovery-server.ts b/packages/dvmcp-discovery/src/discovery-server.ts
index fc48b68..2d41bf4 100644
--- a/packages/dvmcp-discovery/src/discovery-server.ts
+++ b/packages/dvmcp-discovery/src/discovery-server.ts
@@ -31,12 +31,16 @@ export class DiscoveryServer {
     });
 
     this.toolRegistry = new ToolRegistry(this.mcpServer);
-    this.toolExecutor = new ToolExecutor(this.relayHandler, this.keyManager);
+    this.toolExecutor = new ToolExecutor(
+      this.relayHandler,
+      this.keyManager,
+      this.toolRegistry
+    );
 
     this.toolRegistry.setExecutionCallback(async (toolId, args) => {
       const tool = this.toolRegistry.getTool(toolId);
       if (!tool) throw new Error('Tool not found');
-      return this.toolExecutor.executeTool(tool, args);
+      return this.toolExecutor.executeTool(toolId, tool, args);
     });
   }
 
@@ -62,7 +66,7 @@ export class DiscoveryServer {
 
       for (const tool of announcement.tools) {
         const toolId = `${tool.name}:${event.pubkey.slice(0, 4)}`;
-        this.toolRegistry.registerTool(toolId, tool);
+        this.toolRegistry.registerTool(toolId, tool, event.pubkey);
       }
     } catch (error) {
       console.error('Error processing DVM announcement:', error);
diff --git a/packages/dvmcp-discovery/src/tool-executor.ts b/packages/dvmcp-discovery/src/tool-executor.ts
index 5fa24cc..da9b79b 100644
--- a/packages/dvmcp-discovery/src/tool-executor.ts
+++ b/packages/dvmcp-discovery/src/tool-executor.ts
@@ -2,6 +2,7 @@ import { type Event } from 'nostr-tools';
 import { RelayHandler } from '@dvmcp/commons/nostr/relay-handler';
 import { createKeyManager } from '@dvmcp/commons/nostr/key-manager';
 import { type Tool } from '@modelcontextprotocol/sdk/types.js';
+import { ToolRegistry } from './tool-registry.js';
 import {
   TOOL_REQUEST_KIND,
   TOOL_RESPONSE_KIND,
@@ -19,12 +20,17 @@ export class ToolExecutor {
 
   constructor(
     private relayHandler: RelayHandler,
-    private keyManager: ReturnType<typeof createKeyManager>
+    private keyManager: ReturnType<typeof createKeyManager>,
+    private toolRegistry: ToolRegistry
   ) {}
 
-  public async executeTool(tool: Tool, params: unknown): Promise<unknown> {
+  public async executeTool(
+    toolId: string,
+    tool: Tool,
+    params: unknown
+  ): Promise<unknown> {
     return new Promise((resolve, reject) => {
-      const request = this.createToolRequest(tool, params);
+      const request = this.createToolRequest(toolId, tool, params);
       const executionId = request.id;
       const context = this.createExecutionContext(executionId);
 
@@ -102,7 +108,11 @@ export class ToolExecutor {
     }
   }
 
-  private createToolRequest(tool: Tool, params: unknown): Event {
+  private createToolRequest(
+    toolId: string,
+    tool: Tool,
+    params: unknown
+  ): Event {
     const request = this.keyManager.createEventTemplate(TOOL_REQUEST_KIND);
 
     const parameters =
@@ -111,12 +121,17 @@ export class ToolExecutor {
         ? {}
         : params;
 
+    const toolInfo = this.toolRegistry.getToolInfo(toolId);
+    if (!toolInfo) throw new Error(`Tool ${toolId} not found`);
+
     request.content = JSON.stringify({
       name: tool.name,
       parameters,
+      providerPubkey: toolInfo.providerPubkey,
     });
 
     request.tags.push(['c', 'execute-tool']);
+    request.tags.push(['p', toolInfo.providerPubkey]);
     return this.keyManager.signEvent(request);
   }
 }
diff --git a/packages/dvmcp-discovery/src/tool-registry.ts b/packages/dvmcp-discovery/src/tool-registry.ts
index 15a5b8b..69589b8 100644
--- a/packages/dvmcp-discovery/src/tool-registry.ts
+++ b/packages/dvmcp-discovery/src/tool-registry.ts
@@ -4,14 +4,19 @@ import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
 import { z } from 'zod';
 
 export class ToolRegistry {
-  private discoveredTools: Map<string, Tool> = new Map();
+  private discoveredTools: Map<string, { tool: Tool; providerPubkey: string }> =
+    new Map();
 
   constructor(private mcpServer: McpServer) {}
 
-  public registerTool(toolId: string, tool: Tool): void {
+  public registerTool(
+    toolId: string,
+    tool: Tool,
+    providerPubkey: string
+  ): void {
     try {
       ToolSchema.parse(tool);
-      this.discoveredTools.set(toolId, tool);
+      this.discoveredTools.set(toolId, { tool, providerPubkey });
       this.registerWithMcp(toolId, tool);
     } catch (error) {
       console.error(`Invalid MCP tool format for ${toolId}:`, error);
@@ -19,12 +24,16 @@ export class ToolRegistry {
     }
   }
 
-  public getTool(toolId: string): Tool | undefined {
+  public getToolInfo(toolId: string) {
     return this.discoveredTools.get(toolId);
   }
 
+  public getTool(toolId: string): Tool | undefined {
+    return this.discoveredTools.get(toolId)?.tool;
+  }
+
   public listTools(): Tool[] {
-    return Array.from(this.discoveredTools.values());
+    return Array.from(this.discoveredTools.values()).map(({ tool }) => tool);
   }
 
   public clear(): void {