diff --git a/packages/codemode/src/tool-runtime.ts b/packages/codemode/src/tool-runtime.ts
index f1e189f733..5200c13b26 100644
--- a/packages/codemode/src/tool-runtime.ts
+++ b/packages/codemode/src/tool-runtime.ts
@@ -342,7 +342,6 @@ export type DiscoveryPlan = {
 
 export type SearchEntry = {
   readonly description: ToolDescription
-  readonly namespace: string
   readonly searchText: string
 }
 
@@ -373,7 +372,11 @@ const makeSearchTool = (searchIndex: ReadonlyArray<SearchEntry>): Tool => ({
       const scoped =
         request.namespace === undefined
           ? searchIndex
-          : searchIndex.filter((entry) => entry.namespace === request.namespace)
+          : searchIndex.filter(
+              (entry) =>
+                entry.description.path === request.namespace ||
+                entry.description.path.startsWith(`${request.namespace}.`),
+            )
       const trimmed = query.trim()
       const pathQuery = trimmed.startsWith("tools.") ? trimmed.slice("tools.".length) : trimmed
       const exact =
@@ -428,7 +431,6 @@ export const searchSignature = (() => {
 
 const toSearchEntry = <R>(path: string, tool: Tool<R>, description: ToolDescription): SearchEntry => ({
   description,
-  namespace: path.split(".", 1)[0]!,
   searchText: [
     path,
     tool.description,
diff --git a/packages/codemode/test/tool-paths.test.ts b/packages/codemode/test/tool-paths.test.ts
index 3cc92d6dfc..b90b719444 100644
--- a/packages/codemode/test/tool-paths.test.ts
+++ b/packages/codemode/test/tool-paths.test.ts
@@ -54,6 +54,27 @@ describe("dotted tool names", () => {
     expect(flat.catalog()[0]?.path).toBe("issues.list")
     expect(await value(flat, `return await tools.issues.list({})`)).toBe("flat")
   })
+
+  test("search scopes to a nested namespace subtree", async () => {
+    const nested = CodeMode.make({
+      tools: {
+        slack: {
+          admin: echo("Admin", "admin"),
+          "admin.invite": echo("Invite", "invite"),
+          "admin.users.list": echo("List users", "users"),
+          "administrator.list": echo("List administrators", "administrators"),
+          read: echo("Read Slack", "read"),
+        },
+      },
+    })
+
+    const result = await value(nested, `return search({ query: "", namespace: "slack.admin" })`)
+    expect((result as { items: Array<{ path: string }> }).items.map((item) => item.path)).toEqual([
+      "tools.slack.admin",
+      "tools.slack.admin.invite",
+      "tools.slack.admin.users.list",
+    ])
+  })
 })
 
 describe("callable namespaces", () => {