diff --git a/package.json b/package.json
index 51bc66f..080e838 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "toolception",
-  "version": "0.2.3",
+  "version": "0.2.4",
   "private": false,
   "type": "module",
   "main": "dist/index.js",
diff --git a/src/http/FastifyTransport.ts b/src/http/FastifyTransport.ts
index 03a5163..a466912 100644
--- a/src/http/FastifyTransport.ts
+++ b/src/http/FastifyTransport.ts
@@ -114,10 +114,12 @@ export class FastifyTransport {
         let bundle = useCache ? this.clientCache.get(clientId) : null;
         if (!bundle) {
           const created = this.createBundle();
+          const providedSessions = (created as any).sessions;
           bundle = {
             server: created.server,
             orchestrator: created.orchestrator,
-            sessions: new Map(),
+            sessions:
+              providedSessions instanceof Map ? providedSessions : new Map(),
           };
           if (useCache) this.clientCache.set(clientId, bundle);
         }
@@ -230,6 +232,17 @@ export class FastifyTransport {
             id: null,
           };
         }
+        try {
+          // Best-effort close and evict
+          if (typeof (transport as any).close === "function") {
+            try {
+              await (transport as any).close();
+            } catch {}
+          }
+        } finally {
+          if (transport?.sessionId) bundle.sessions.delete(transport.sessionId);
+          else bundle.sessions.delete(sessionId);
+        }
         reply.code(204).send();
         return reply;
       }
diff --git a/src/server/createMcpServer.ts b/src/server/createMcpServer.ts
index ab33aeb..8a2e86f 100644
--- a/src/server/createMcpServer.ts
+++ b/src/server/createMcpServer.ts
@@ -71,9 +71,12 @@ export async function createMcpServer(options: CreateMcpServerOptions) {
     () => {
       // Create a server + orchestrator bundle
       // for a new client when needed
-      const createdServer: McpServer =
-        mode === "DYNAMIC" ? options.createServer() : baseServer;
-      const orchestrator = new ServerOrchestrator({
+      if (mode === "STATIC") {
+        // Reuse the base server and orchestrator to avoid duplicate registrations
+        return { server: baseServer, orchestrator };
+      }
+      const createdServer: McpServer = options.createServer();
+      const createdOrchestrator = new ServerOrchestrator({
         server: createdServer,
         catalog: options.catalog,
         moduleLoaders: options.moduleLoaders,
@@ -86,7 +89,7 @@ export async function createMcpServer(options: CreateMcpServerOptions) {
             ? options.registerMetaTools
             : mode === "DYNAMIC",
       });
-      return { server: createdServer, orchestrator };
+      return { server: createdServer, orchestrator: createdOrchestrator };
     },
     options.http,
     options.configSchema
diff --git a/tests/createMcpServer.test.ts b/tests/createMcpServer.test.ts
index 09d28a1..4a15105 100644
--- a/tests/createMcpServer.test.ts
+++ b/tests/createMcpServer.test.ts
@@ -124,4 +124,40 @@ describe("createMcpServer", () => {
     expect(s1.calls.includes("list_tools")).toBe(true);
     expect(s2.calls.includes("list_tools")).toBe(true);
   });
+
+  it("does not re-register tools in STATIC mode across multiple clients", async () => {
+    const f = makeFakeServerFactory();
+    const staticCatalog = {
+      core: {
+        name: "Core",
+        description: "",
+        tools: [
+          {
+            name: "ping",
+            description: "",
+            inputSchema: {},
+            handler: async () => ({ content: [{ type: "text", text: "pong" }] }),
+          },
+        ],
+      },
+    } as any;
+
+    await createMcpServer({
+      catalog: staticCatalog,
+      startup: { mode: "STATIC", toolsets: ["core"] },
+      createServer: f.createServer,
+    });
+
+    const base = f.created[0];
+    // One registration at startup, namespaced by toolset key
+    expect(base.calls.filter((n) => n === "core.ping").length).toBe(1);
+
+    const bundleFactory = (FastifyTransportMock as any).lastArgs?.[1];
+    // Simulate two more clients (bundles)
+    bundleFactory();
+    bundleFactory();
+
+    // No additional registrations should have occurred on the shared server
+    expect(base.calls.filter((n) => n === "core.ping").length).toBe(1);
+  });
 });
diff --git a/tests/fastifyTransport.test.ts b/tests/fastifyTransport.test.ts
index ed121ed..6cfa669 100644
--- a/tests/fastifyTransport.test.ts
+++ b/tests/fastifyTransport.test.ts
@@ -41,4 +41,61 @@ describe("FastifyTransport", () => {
 
     await transport.stop();
   });
+
+  it("DELETE /mcp evicts session after close", async () => {
+    // Fake server that supports connect()
+    const server: any = {
+      async connect(_t: any) {
+        // no-op
+      },
+    };
+    const resolver = new ModuleResolver({
+      catalog: { core: { name: "Core", description: "", tools: [] } } as any,
+    });
+    const manager = new DynamicToolManager({ server, resolver });
+
+    const app = Fastify({ logger: false });
+    // Stub createBundle with a minimal streamable transport-like object
+    const sessions = new Map<string, any>();
+    const bundle = { server, orchestrator: {} as any, sessions } as any;
+
+    const transport = new FastifyTransport(
+      manager,
+      () => bundle,
+      { port: 0, logger: false, app }
+    );
+    await transport.start();
+
+    const clientId = "c1";
+    // Seed bundle in cache with a non-initialize POST (will 400 but caches bundle)
+    await app.inject({
+      method: "POST",
+      url: "/mcp",
+      headers: { "mcp-client-id": clientId },
+      payload: { jsonrpc: "2.0", id: 1, method: "unknown", params: {} },
+    });
+
+    // Now create a fake session inside the cached bundle
+    const createdSessionId = "s-1";
+    const storedTransport: any = {
+      sessionId: createdSessionId,
+      async handleRequest() {},
+      async close() {
+        this._closed = true;
+      },
+    };
+    sessions.set(createdSessionId, storedTransport);
+
+    // Attempt DELETE
+    const res = await app.inject({
+      method: "DELETE",
+      url: "/mcp",
+      headers: { "mcp-client-id": clientId, "mcp-session-id": createdSessionId },
+    });
+    expect(res.statusCode).toBe(204);
+    expect(storedTransport._closed).toBe(true);
+    expect(sessions.has(createdSessionId)).toBe(false);
+
+    await transport.stop();
+  });
 });