diff --git a/apps/web/app/(authed)/memories/[id]/page.tsx b/apps/web/app/(authed)/memories/[id]/page.tsx
index e3d0ac0..b4e1695 100644
--- a/apps/web/app/(authed)/memories/[id]/page.tsx
+++ b/apps/web/app/(authed)/memories/[id]/page.tsx
@@ -1,6 +1,6 @@
 import Link from "next/link";
 import { notFound } from "next/navigation";
-import { and, eq, isNull } from "drizzle-orm";
+import { and, desc, eq, isNull } from "drizzle-orm";
 import { auth } from "@/auth";
 import { db } from "@/lib/db/client";
 import { memories, projects } from "@/lib/db/schema";
@@ -48,6 +48,15 @@ export default async function MemoryDetailPage({
 
   const isEditing = edit === "1";
 
+  const projectList = isEditing
+    ? await db
+        .select({ key: projects.key, displayName: projects.displayName })
+        .from(projects)
+        .where(eq(projects.userId, userId))
+        .orderBy(desc(projects.updatedAt))
+        .limit(50)
+    : [];
+
   return (
     <Container className="pt-6 max-w-3xl">
       <PageHeader
@@ -81,6 +90,40 @@ export default async function MemoryDetailPage({
           <CardBody>
             <form action={updateMemoryAction} className="space-y-4">
               <input type="hidden" name="id" value={m.id} />
+              <div>
+                <Label htmlFor="scope">Scope</Label>
+                <select
+                  id="scope"
+                  name="scope"
+                  defaultValue={m.scope}
+                  className="mt-1 h-9 px-2 rounded-md bg-surface-1 border border-border text-fg text-sm w-full"
+                >
+                  <option value="project">Project — attached to a project</option>
+                  <option value="user">User — global across all projects</option>
+                </select>
+              </div>
+              <div>
+                <Label htmlFor="project" hint="Required for project scope">
+                  Project key
+                </Label>
+                <Input
+                  id="project"
+                  name="project"
+                  defaultValue={m.projectKey ?? ""}
+                  placeholder="repo name, slug, or any stable string"
+                  list="project-list"
+                  className="mt-1"
+                />
+                {projectList.length > 0 ? (
+                  <datalist id="project-list">
+                    {projectList.map((p) => (
+                      <option key={p.key} value={p.key}>
+                        {p.displayName ?? p.key}
+                      </option>
+                    ))}
+                  </datalist>
+                ) : null}
+              </div>
               <div>
                 <Label htmlFor="content">Content</Label>
                 <Textarea
diff --git a/apps/web/lib/mcp/tools.ts b/apps/web/lib/mcp/tools.ts
index 2cc63b7..db69771 100644
--- a/apps/web/lib/mcp/tools.ts
+++ b/apps/web/lib/mcp/tools.ts
@@ -311,13 +311,24 @@ const memoryDelete: ToolDef = {
 const memoryUpdate: ToolDef = {
   name: "memory.update",
   description:
-    "Edit an existing memory in place — for correcting a stored fact, expanding it with new detail, or adjusting tags. Preserves the memory's id (so callers referencing it don't break) and re-embeds automatically when content changes. Use this — not delete + write — whenever you're refining what's already there.",
+    "Edit an existing memory in place — for correcting a stored fact, expanding it with new detail, adjusting tags, or moving it to a different scope/project. Preserves the memory's id (so callers referencing it don't break) and re-embeds automatically when content changes. Pass `scope` and/or `project` to reclassify a memory between user-global and project-attached without recreating it. Use this — not delete + write — whenever you're refining what's already there.",
   inputSchema: {
     type: "object",
     properties: {
       id: { type: "string", format: "uuid" },
       content: { type: "string", description: "Replacement content (1–64,000 chars)." },
       tags: { type: "array", items: { type: "string" }, description: "Replacement tag list." },
+      scope: {
+        type: "string",
+        enum: ["project", "user"],
+        description:
+          "New scope. When 'project', `project` must be set. When 'user', `project` must be omitted.",
+      },
+      project: {
+        type: "string",
+        description:
+          "Project key the memory should attach to (required and only valid when scope='project'). Project is upserted if it doesn't exist.",
+      },
     },
     required: ["id"],
   },
@@ -325,9 +336,16 @@ const memoryUpdate: ToolDef = {
     const parsed = MemoryUpdateInput.safeParse(args);
     if (!parsed.success) return err(parsed.error.message);
 
-    const existing = await db
-      .select({ id: memories.id, content: memories.content })
+    const existingRows = await db
+      .select({
+        id: memories.id,
+        content: memories.content,
+        scope: memories.scope,
+        projectId: memories.projectId,
+        projectKey: projects.key,
+      })
       .from(memories)
+      .leftJoin(projects, eq(memories.projectId, projects.id))
       .where(
         and(
           eq(memories.id, parsed.data.id),
@@ -336,30 +354,76 @@ const memoryUpdate: ToolDef = {
         ),
       )
       .limit(1);
-    if (!existing[0]) return err("not found");
+    const existing = existingRows[0];
+    if (!existing) return err("not found");
 
     const update: Record<string, unknown> = { updatedAt: new Date() };
     if (parsed.data.tags !== undefined) update.tags = parsed.data.tags;
-    if (parsed.data.content !== undefined && parsed.data.content !== existing[0].content) {
+    if (parsed.data.content !== undefined && parsed.data.content !== existing.content) {
       update.content = parsed.data.content;
       update.embedding = await embedText(parsed.data.content);
     }
 
+    let scopeChanged = false;
+    let projectChanged = false;
+    let newProjectKey: string | null = existing.projectKey ?? null;
+
+    if (parsed.data.scope !== undefined) {
+      if (parsed.data.scope === "user") {
+        if (existing.scope !== "user") {
+          update.scope = "user";
+          scopeChanged = true;
+        }
+        if (existing.projectId !== null) {
+          update.projectId = null;
+          projectChanged = true;
+          newProjectKey = null;
+        }
+      } else {
+        // scope === 'project' — schema refine guarantees `project` is set
+        const projectKey = parsed.data.project!;
+        const projectId = await resolveProjectId(ctx, projectKey);
+        if (!projectId) {
+          return err(`unknown project '${projectKey}'; call project.identify first`);
+        }
+        if (existing.scope !== "project") {
+          update.scope = "project";
+          scopeChanged = true;
+        }
+        if (existing.projectId !== projectId) {
+          update.projectId = projectId;
+          projectChanged = true;
+          newProjectKey = projectKey;
+        }
+      }
+    }
+
     const updated = await db
       .update(memories)
       .set(update)
       .where(eq(memories.id, parsed.data.id))
       .returning({ id: memories.id, updatedAt: memories.updatedAt });
 
+    const auditFields = Object.keys(update).filter((k) => k !== "updatedAt");
+    const auditPayload: Record<string, unknown> = { fields: auditFields };
+    if (scopeChanged || projectChanged) {
+      auditPayload.scope = {
+        from: existing.scope,
+        to: update.scope ?? existing.scope,
+      };
+      auditPayload.projectKey = {
+        from: existing.projectKey ?? null,
+        to: newProjectKey,
+      };
+    }
+
     await db.insert(auditLog).values({
       userId: ctx.userId,
       actor: "mcp",
       action: "memory.update",
       entityType: "memory",
       entityId: updated[0]!.id,
-      payload: {
-        fields: Object.keys(update).filter((k) => k !== "updatedAt"),
-      },
+      payload: auditPayload,
     });
 
     return ok(updated[0]!, `updated memory ${updated[0]!.id}`);
diff --git a/apps/web/lib/memory-actions.ts b/apps/web/lib/memory-actions.ts
index dd48bf0..6c3ca2e 100644
--- a/apps/web/lib/memory-actions.ts
+++ b/apps/web/lib/memory-actions.ts
@@ -113,41 +113,100 @@ export async function updateMemoryAction(formData: FormData) {
   const userId = await requireUserId();
 
   const id = String(formData.get("id") ?? "");
+  const rawScope = formData.get("scope");
+  const rawProject = (formData.get("project") as string | null)?.trim() || undefined;
   const payload = {
     id,
     content: ((formData.get("content") as string | null) ?? "").trim() || undefined,
     tags: parseTags(formData.get("tags")),
+    scope:
+      rawScope === "project" || rawScope === "user"
+        ? (rawScope as "project" | "user")
+        : undefined,
+    project: rawProject,
   };
   const parsed = MemoryUpdateInput.safeParse(payload);
   if (!parsed.success) {
     throw new Error(parsed.error.issues.map((i) => i.message).join("; "));
   }
 
-  const existing = await db
-    .select({ id: memories.id, content: memories.content })
+  const existingRows = await db
+    .select({
+      id: memories.id,
+      content: memories.content,
+      scope: memories.scope,
+      projectId: memories.projectId,
+      projectKey: projects.key,
+    })
     .from(memories)
+    .leftJoin(projects, eq(memories.projectId, projects.id))
     .where(
       and(eq(memories.id, parsed.data.id), eq(memories.userId, userId), isNull(memories.deletedAt)),
     )
     .limit(1);
-  if (!existing[0]) throw new Error("not found");
+  const existing = existingRows[0];
+  if (!existing) throw new Error("not found");
 
   const update: Record<string, unknown> = { updatedAt: new Date() };
   if (parsed.data.tags !== undefined) update.tags = parsed.data.tags;
-  if (parsed.data.content !== undefined && parsed.data.content !== existing[0].content) {
+  if (parsed.data.content !== undefined && parsed.data.content !== existing.content) {
     update.content = parsed.data.content;
     update.embedding = await embedText(parsed.data.content);
   }
 
+  let scopeChanged = false;
+  let projectChanged = false;
+  let newProjectKey: string | null = existing.projectKey ?? null;
+
+  if (parsed.data.scope !== undefined) {
+    if (parsed.data.scope === "user") {
+      if (existing.scope !== "user") {
+        update.scope = "user";
+        scopeChanged = true;
+      }
+      if (existing.projectId !== null) {
+        update.projectId = null;
+        projectChanged = true;
+        newProjectKey = null;
+      }
+    } else {
+      // scope === 'project' — schema refine guarantees project is set
+      const projectKey = parsed.data.project!;
+      const projectId = await upsertProject(userId, projectKey);
+      if (existing.scope !== "project") {
+        update.scope = "project";
+        scopeChanged = true;
+      }
+      if (existing.projectId !== projectId) {
+        update.projectId = projectId;
+        projectChanged = true;
+        newProjectKey = projectKey;
+      }
+    }
+  }
+
   await db.update(memories).set(update).where(eq(memories.id, parsed.data.id));
 
+  const auditFields = Object.keys(update).filter((k) => k !== "updatedAt");
+  const auditPayload: Record<string, unknown> = { fields: auditFields };
+  if (scopeChanged || projectChanged) {
+    auditPayload.scope = {
+      from: existing.scope,
+      to: update.scope ?? existing.scope,
+    };
+    auditPayload.projectKey = {
+      from: existing.projectKey ?? null,
+      to: newProjectKey,
+    };
+  }
+
   await db.insert(auditLog).values({
     userId,
     actor: "web",
     action: "memory.update",
     entityType: "memory",
     entityId: parsed.data.id,
-    payload: { fields: Object.keys(update).filter((k) => k !== "updatedAt") },
+    payload: auditPayload,
   });
 
   revalidatePath(`/memories/${parsed.data.id}`);
diff --git a/packages/schemas/src/index.ts b/packages/schemas/src/index.ts
index 16a6134..c7aaa9f 100644
--- a/packages/schemas/src/index.ts
+++ b/packages/schemas/src/index.ts
@@ -46,9 +46,25 @@ export const MemoryUpdateInput = z.object({
   id: z.string().uuid(),
   content: MemoryContent.optional(),
   tags: Tags.optional(),
-}).refine((v) => v.content !== undefined || v.tags !== undefined, {
-  message: "memory.update requires content or tags",
-});
+  scope: MemoryScope.optional(),
+  project: ProjectKey.optional(),
+})
+  .refine(
+    (v) =>
+      v.content !== undefined ||
+      v.tags !== undefined ||
+      v.scope !== undefined ||
+      v.project !== undefined,
+    { message: "memory.update requires content, tags, scope, or project" },
+  )
+  .refine(
+    (v) => v.scope !== "project" || (v.project !== undefined && v.project !== ""),
+    { message: "scope='project' requires a non-empty project key" },
+  )
+  .refine(
+    (v) => v.scope !== "user" || v.project === undefined || v.project === "",
+    { message: "scope='user' cannot have a project key" },
+  );
 export type MemoryUpdateInput = z.infer<typeof MemoryUpdateInput>;
 
 export const MemorySearchInput = z.object({