diff --git a/apps/mobile/src/features/connection/ConnectionDiagnosisDetails.tsx b/apps/mobile/src/features/connection/ConnectionDiagnosisDetails.tsx
index df0e8c165929e..c042f8df3ef8f 100644
--- a/apps/mobile/src/features/connection/ConnectionDiagnosisDetails.tsx
+++ b/apps/mobile/src/features/connection/ConnectionDiagnosisDetails.tsx
@@ -38,7 +38,7 @@ export function useConnectionDiagnosis(
   const relayOnly =
     connectionRoutes(presentation.entry).length === 1 && hasRelayRoute(presentation.entry);
   const diagnosis = presentConnectionDiagnosis({
-    hostLabel: presentation.entry.target.label,
+    hostLabel: presentation.label,
     state,
     via: relayOnly ? "relay" : "direct",
     clientVersion: Constants.expoConfig?.version,
diff --git a/apps/mobile/src/features/connection/ConnectionEnvironmentRow.tsx b/apps/mobile/src/features/connection/ConnectionEnvironmentRow.tsx
index aa332b407b2e3..7dff941837c4b 100644
--- a/apps/mobile/src/features/connection/ConnectionEnvironmentRow.tsx
+++ b/apps/mobile/src/features/connection/ConnectionEnvironmentRow.tsx
@@ -49,15 +49,18 @@ export function ConnectionEnvironmentRow(props: {
     updates: { readonly label: string; readonly displayUrl: string },
   ) => Promise<AtomCommandResult<unknown, unknown>>;
 }) {
-  const [label, setLabel] = useState(props.environment.environmentLabel);
+  const presentation = useAtomValue(
+    environmentPresentations.presentationAtom(props.environment.environmentId),
+  );
+  // Edit the saved label; the displayed one may be the environment's own custom name.
+  const [label, setLabel] = useState(
+    presentation?.entry.target.label ?? props.environment.environmentLabel,
+  );
   const [url, setUrl] = useState(props.environment.displayUrl);
   const serverConfig = useAtomValue(
     serverEnvironment.configValueAtom(props.environment.environmentId),
   );
   const unsupported = props.environment.connectionState === "unsupported";
-  const presentation = useAtomValue(
-    environmentPresentations.presentationAtom(props.environment.environmentId),
-  );
   const canRetry = presentation !== null && hasSavedBearerRoute(presentation.entry);
   const { diagnosis, state: connectionState } = useConnectionDiagnosis(
     props.environment.environmentId,
diff --git a/apps/mobile/src/features/connection/PullRequestRoutingSettings.tsx b/apps/mobile/src/features/connection/PullRequestRoutingSettings.tsx
index 44383db74b2ad..afa7793fa4b2f 100644
--- a/apps/mobile/src/features/connection/PullRequestRoutingSettings.tsx
+++ b/apps/mobile/src/features/connection/PullRequestRoutingSettings.tsx
@@ -13,6 +13,7 @@ import { Pressable, View } from "react-native";
 import { AppText as Text } from "../../components/ui/AppText";
 import { SymbolView } from "../../components/ui/AppSymbol";
 import { environmentCatalog } from "../../connection/catalog";
+import { environmentPresentations } from "../../state/presentation";
 import { useAtomCommand } from "../../state/use-atom-command";
 import { SettingsSection } from "../settings/components/SettingsSection";
 
@@ -38,6 +39,7 @@ const options: ReadonlyArray<{
 export function PullRequestRoutingSettings() {
   const catalog = useAtomValue(environmentCatalog.catalogValueAtom);
   const permissions = useAtomValue(environmentCatalog.pullRequestRoutingPermissionsValueAtom);
+  const presentations = useAtomValue(environmentPresentations.presentationsAtom);
   const update = useAtomCommand(environmentCatalog.setPullRequestRoutingPermission);
   const [expanded, setExpanded] = useState<string | null>(null);
   const [saving, setSaving] = useState(false);
@@ -48,6 +50,7 @@ export function PullRequestRoutingSettings() {
       <SettingsSection title="Pull request routing">
         {[...catalog.entries.values()].map((entry) => {
           const environmentId = entry.target.environmentId;
+          const label = presentations.get(environmentId)?.label ?? entry.target.label;
           const selected = pullRequestRoutingPermissionFor(entry, permissions);
           const disabled =
             !catalog.isReady || saving || pullRequestRoutingConnectionKey(entry) === null;
@@ -55,15 +58,13 @@ export function PullRequestRoutingSettings() {
             <View key={environmentId}>
               <Pressable
                 accessibilityRole="button"
-                accessibilityLabel={`${entry.target.label} pull request routing`}
+                accessibilityLabel={`${label} pull request routing`}
                 accessibilityState={{ expanded: expanded === environmentId }}
                 className="flex-row items-center gap-3 p-4"
                 onPress={() => setExpanded(expanded === environmentId ? null : environmentId)}
               >
                 <View className="min-w-0 flex-1 gap-0.5">
-                  <Text className="text-base font-t3-bold text-foreground">
-                    {entry.target.label}
-                  </Text>
+                  <Text className="text-base font-t3-bold text-foreground">{label}</Text>
                   <Text className="text-xs text-foreground-muted" numberOfLines={1}>
                     {connectionCatalogDisplayUrl(entry) ?? "T3 Connect"}
                   </Text>
diff --git a/apps/mobile/src/features/files/WorkspaceFilePreviewError.tsx b/apps/mobile/src/features/files/WorkspaceFilePreviewError.tsx
index 79df6d05c700f..ac47d604ddc51 100644
--- a/apps/mobile/src/features/files/WorkspaceFilePreviewError.tsx
+++ b/apps/mobile/src/features/files/WorkspaceFilePreviewError.tsx
@@ -26,7 +26,7 @@ export function WorkspaceFilePreviewError(props: {
     return (
       <View className="flex-1 bg-sheet">
         <EnvironmentConnectionNotice
-          environmentLabel={environment.presentation?.entry.target.label ?? "Environment"}
+          environmentLabel={environment.presentation?.label ?? "Environment"}
           connection={
             environment.presentation?.connection ?? {
               phase: "available",
diff --git a/apps/mobile/src/features/review/ReviewSheet.tsx b/apps/mobile/src/features/review/ReviewSheet.tsx
index 55e4398ec24b6..09e90937e7f2d 100644
--- a/apps/mobile/src/features/review/ReviewSheet.tsx
+++ b/apps/mobile/src/features/review/ReviewSheet.tsx
@@ -695,7 +695,7 @@ export function ReviewSheet(props: ReviewSheetProps) {
           {showConnectionNotice ? (
             <View className="flex-1" style={{ paddingTop: topContentInset }}>
               <EnvironmentConnectionNotice
-                environmentLabel={environment.presentation?.entry.target.label ?? "Environment"}
+                environmentLabel={environment.presentation?.label ?? "Environment"}
                 connection={
                   environment.presentation?.connection ?? {
                     phase: "available",
diff --git a/apps/mobile/src/features/terminal/ThreadTerminalRouteScreen.tsx b/apps/mobile/src/features/terminal/ThreadTerminalRouteScreen.tsx
index de0c090f93994..fe6224fd40d53 100644
--- a/apps/mobile/src/features/terminal/ThreadTerminalRouteScreen.tsx
+++ b/apps/mobile/src/features/terminal/ThreadTerminalRouteScreen.tsx
@@ -890,7 +890,7 @@ function ThreadTerminal(props: {
           {!isEnvironmentReady ? (
             <EnvironmentConnectionNotice
               environmentLabel={
-                environment.presentation?.entry.target.label ??
+                environment.presentation?.label ??
                 selectedEnvironmentConnection?.environmentLabel ??
                 "Environment"
               }
diff --git a/apps/mobile/src/features/usage/UsageLimitsSection.tsx b/apps/mobile/src/features/usage/UsageLimitsSection.tsx
index 3cd009cf67cf9..349458bcfc00f 100644
--- a/apps/mobile/src/features/usage/UsageLimitsSection.tsx
+++ b/apps/mobile/src/features/usage/UsageLimitsSection.tsx
@@ -340,7 +340,7 @@ export function useRefreshLimits(
   );
   const failedLabels = selected
     .filter(([environmentId]) => failedIds.has(environmentId))
-    .map(([, presentation]) => presentation.entry.target.label);
+    .map(([, presentation]) => presentation.label);
 
   const refresh = (afterPending: boolean) =>
     Promise.all(
diff --git a/apps/mobile/src/state/environments.ts b/apps/mobile/src/state/environments.ts
index 776a615f46afb..45fcf91b4abd8 100644
--- a/apps/mobile/src/state/environments.ts
+++ b/apps/mobile/src/state/environments.ts
@@ -13,7 +13,6 @@ import { useEnvironmentQuery } from "./query";
 
 export interface EnvironmentPresentation extends BaseEnvironmentPresentation {
   readonly environmentId: EnvironmentId;
-  readonly label: string;
   readonly displayUrl: string | null;
   readonly relayManaged: boolean;
 }
@@ -25,7 +24,6 @@ export function projectEnvironmentPresentation(
   return {
     ...presentation,
     environmentId,
-    label: presentation.entry.target.label,
     displayUrl: connectionCatalogDisplayUrl(presentation.entry),
     relayManaged: hasRelayRoute(presentation.entry),
   };
diff --git a/apps/mobile/src/state/remote-environment-projections.test.ts b/apps/mobile/src/state/remote-environment-projections.test.ts
index 92fbd512e15b1..33e67b70e3f9c 100644
--- a/apps/mobile/src/state/remote-environment-projections.test.ts
+++ b/apps/mobile/src/state/remote-environment-projections.test.ts
@@ -28,8 +28,10 @@ function presentation(
   endpoint: string = environmentId,
   serverConfig: ServerConfig | null = null,
 ): EnvironmentPresentation {
+  const entry = { target: target(environmentId, endpoint), profile: Option.none(), enabled: true };
   return {
-    entry: { target: target(environmentId, endpoint), profile: Option.none(), enabled: true },
+    entry,
+    label: entry.target.label,
     connection: { phase: "connected", error: null, traceId: null },
     serverConfig,
   };
diff --git a/apps/mobile/src/state/remote-environment-projections.ts b/apps/mobile/src/state/remote-environment-projections.ts
index c70acce6d932f..bf2df00b0d018 100644
--- a/apps/mobile/src/state/remote-environment-projections.ts
+++ b/apps/mobile/src/state/remote-environment-projections.ts
@@ -21,6 +21,7 @@ export function createRemoteEnvironmentProjectionAtoms(input: {
 }) {
   const savedConnectionAtom = Atom.family((environmentId: EnvironmentId) => {
     let previousEntry: EnvironmentPresentation["entry"] | null = null;
+    let previousLabel: string | null = null;
     let previousPrepared: PreparedConnection | null = null;
     let previous: SavedRemoteConnection | null = null;
 
@@ -28,6 +29,7 @@ export function createRemoteEnvironmentProjectionAtoms(input: {
       const presentation = get(input.presentationAtom(environmentId));
       if (presentation === null) {
         previousEntry = null;
+        previousLabel = null;
         previousPrepared = null;
         previous = null;
         return null;
@@ -37,6 +39,7 @@ export function createRemoteEnvironmentProjectionAtoms(input: {
       if (
         previous !== null &&
         presentation.entry === previousEntry &&
+        presentation.label === previousLabel &&
         prepared === previousPrepared
       ) {
         return previous;
@@ -58,10 +61,11 @@ export function createRemoteEnvironmentProjectionAtoms(input: {
         : presentation.entry.target._tag === "RelayConnectionTarget";
 
       previousEntry = presentation.entry;
+      previousLabel = presentation.label;
       previousPrepared = prepared;
       previous = {
         environmentId,
-        environmentLabel: presentation.entry.target.label,
+        environmentLabel: presentation.label,
         pairingUrl: displayUrl,
         displayUrl,
         httpBaseUrl,
diff --git a/apps/mobile/src/state/usage.ts b/apps/mobile/src/state/usage.ts
index b0931e175c558..bce7cc727cee7 100644
--- a/apps/mobile/src/state/usage.ts
+++ b/apps/mobile/src/state/usage.ts
@@ -45,7 +45,7 @@ const usageByWindowAtom = Atom.family((windowKey: string) =>
       if (!access.canReadDiagnostics) {
         statuses.push({
           environmentId,
-          label: presentation.entry.target.label,
+          label: presentation.label,
           isConnected: presentation.connection.phase === "connected",
           ...access,
           summary: null,
@@ -57,7 +57,7 @@ const usageByWindowAtom = Atom.family((windowKey: string) =>
       const summary = Option.getOrNull(AsyncResult.value(result));
       statuses.push({
         environmentId,
-        label: presentation.entry.target.label,
+        label: presentation.label,
         isPending: result.waiting,
         isConnected: presentation.connection.phase === "connected",
         canReadDiagnostics: true,
diff --git a/apps/mobile/src/state/workspace-connection-atoms.test.ts b/apps/mobile/src/state/workspace-connection-atoms.test.ts
index 64c7256ca89fb..0fb1e720a80f5 100644
--- a/apps/mobile/src/state/workspace-connection-atoms.test.ts
+++ b/apps/mobile/src/state/workspace-connection-atoms.test.ts
@@ -26,6 +26,7 @@ function presentation(): EnvironmentPresentation {
       enabled: true,
       profile: Option.none(),
     },
+    label: "Mac",
     connection: { phase: "connected", error: null, traceId: null },
     serverConfig: null,
   };
diff --git a/apps/server/src/environment/ServerEnvironment.ts b/apps/server/src/environment/ServerEnvironment.ts
index 4678aff95b736..57c660e4ad5d5 100644
--- a/apps/server/src/environment/ServerEnvironment.ts
+++ b/apps/server/src/environment/ServerEnvironment.ts
@@ -256,6 +256,7 @@ export const make = Effect.gen(function* () {
       serverResolvedCommandContext: true,
       threadStop: true,
       environmentIcon: true,
+      environmentLabel: true,
       projectCloneTracking: true,
       ignoredFileListing: true,
       ...(serverSelfUpdate === null ? {} : { serverSelfUpdate }),
diff --git a/apps/server/src/mcp/toolkits/environment/handlers.test.ts b/apps/server/src/mcp/toolkits/environment/handlers.test.ts
index b4d39bd41c17f..2590f3ce1b7c9 100644
--- a/apps/server/src/mcp/toolkits/environment/handlers.test.ts
+++ b/apps/server/src/mcp/toolkits/environment/handlers.test.ts
@@ -95,3 +95,48 @@ it.effect("refuses a preferences update when the caller's turn ends while it wai
     );
   }),
 );
+
+it.effect("reads the environment by its custom name", () =>
+  Effect.gen(function* () {
+    const layerDependencies = Layer.mergeAll(
+      ThreadCommandExecutor.layer,
+      Layer.succeed(McpInvocationContext.McpInvocationContext, {
+        environmentId,
+        requestNamespace: "provider:preferences",
+        thread: undefined,
+        client: undefined,
+        capabilities: new Set(["orchestration" as const]),
+        issuedAt: 0,
+      }),
+      Layer.mock(ThreadManagement.ThreadManagementService)({}),
+      Layer.mock(Environment.ServerEnvironment)({
+        getDescriptor: Effect.succeed({
+          environmentId,
+          label: "devbox",
+          platform: { os: "linux", arch: "x64" },
+          serverVersion: "0.0.0",
+          capabilities: { repositoryIdentity: false },
+        }),
+      }),
+      Layer.mock(Settings.ServerSettingsService)({
+        getSettings: Effect.succeed({
+          ...DEFAULT_SERVER_SETTINGS,
+          environmentLabel: "MacBook Pro · user2",
+        }),
+      }),
+    );
+    const result = yield* Effect.gen(function* () {
+      const toolkit = yield* EnvironmentToolkit;
+      return yield* toolkit
+        .handle("t3_environment_read", {})
+        .pipe(Stream.unwrap, Stream.runCollect);
+    }).pipe(
+      Effect.provide(
+        McpToolAccess.HandlersLayer.layer(EnvironmentHandlers.layer).pipe(
+          Layer.provideMerge(layerDependencies),
+        ),
+      ),
+    );
+    expect(result.at(-1)?.result).toMatchObject({ label: "MacBook Pro · user2" });
+  }),
+);
diff --git a/apps/server/src/mcp/toolkits/environment/handlers.ts b/apps/server/src/mcp/toolkits/environment/handlers.ts
index fb1716885d6e8..5d5accd13ec6e 100644
--- a/apps/server/src/mcp/toolkits/environment/handlers.ts
+++ b/apps/server/src/mcp/toolkits/environment/handlers.ts
@@ -47,7 +47,7 @@ export const layer = McpToolAccess.toLayer(EnvironmentToolkit, {
       const current = yield* settings.getSettings.pipe(Effect.mapError(unavailable));
       return {
         environmentId: descriptor.environmentId,
-        label: descriptor.label,
+        label: current.environmentLabel ?? descriptor.label,
         serverVersion: descriptor.serverVersion,
         platform: descriptor.platform,
         preferences: preferences(current),
diff --git a/apps/web/src/components/chat/useComposerSend.ts b/apps/web/src/components/chat/useComposerSend.ts
index 597cafb35e92f..26c6bd5f5fff6 100644
--- a/apps/web/src/components/chat/useComposerSend.ts
+++ b/apps/web/src/components/chat/useComposerSend.ts
@@ -545,8 +545,7 @@ export function useComposerSend(input: ComposerSendInput) {
     })[0];
     if (strandedThread) {
       const owner =
-        readEnvironmentPresentation(strandedThread.environmentId)?.entry.target.label ??
-        "its machine";
+        readEnvironmentPresentation(strandedThread.environmentId)?.label ?? "its machine";
       toastManager.add(
         stackedThreadToast({
           type: "warning",
diff --git a/apps/web/src/components/settings/ChatGptWelcomeCoordinator.tsx b/apps/web/src/components/settings/ChatGptWelcomeCoordinator.tsx
index 6b449407abb26..ea8ed10178f72 100644
--- a/apps/web/src/components/settings/ChatGptWelcomeCoordinator.tsx
+++ b/apps/web/src/components/settings/ChatGptWelcomeCoordinator.tsx
@@ -41,7 +41,7 @@ export function ChatGptWelcomeCoordinator() {
               provider.instanceId,
               provider.auth.profileId ?? provider.auth.email ?? "default",
             ]),
-            environmentLabel: presentation.entry.target.label,
+            environmentLabel: presentation.label,
             providerName: provider.displayName ?? "Codex",
           })),
   );
diff --git a/apps/web/src/components/settings/ConnectionsSettings.tsx b/apps/web/src/components/settings/ConnectionsSettings.tsx
index 3aa4a150a4d83..db8eb9df299a3 100644
--- a/apps/web/src/components/settings/ConnectionsSettings.tsx
+++ b/apps/web/src/components/settings/ConnectionsSettings.tsx
@@ -1,5 +1,5 @@
 import { SessionPermissions } from "./SessionPermissions";
-import { ChevronRightIcon, EllipsisIcon } from "lucide-react";
+import { ChevronRightIcon, EllipsisIcon, PencilIcon } from "lucide-react";
 import { useAtomValue } from "@effect/atom-react";
 import { useState } from "react";
 import {
@@ -35,6 +35,7 @@ import { SettingsPageContainer, SettingsRow, SettingsSection } from "./settingsL
 import { LocalEnvironmentSetting } from "./LocalEnvironmentSetting";
 import { searchableSetting } from "./settingsSearch";
 import { EnvironmentIconMenu } from "./EnvironmentIconPicker";
+import { EnvironmentRenameDialog } from "./EnvironmentRenameDialog";
 import { FoldedSettingsSection } from "./FoldedSettingsSection";
 import { LoadBalancingSettings } from "./LoadBalancingSettings";
 import { PullRequestRoutingSettings } from "./PullRequestRoutingSettings";
@@ -61,7 +62,7 @@ import {
 } from "../ui/alert-dialog";
 import { Spinner } from "../ui/spinner";
 import { Select, SelectItem, SelectPopup, SelectTrigger, SelectValue } from "../ui/select";
-import { Menu, MenuPopup, MenuTrigger } from "../ui/menu";
+import { Menu, MenuItem, MenuPopup, MenuTrigger } from "../ui/menu";
 import { Switch } from "../ui/switch";
 import { stackedThreadToast, toastManager } from "../ui/toast";
 import { Tooltip, TooltipPopup, TooltipTrigger } from "../ui/tooltip";
@@ -235,6 +236,7 @@ export function ConnectionsSettings() {
   >(null);
   const [isRevokingOtherDesktopClients, setIsRevokingOtherDesktopClients] = useState(false);
   const [addBackendDialogOpen, setAddBackendDialogOpen] = useState(false);
+  const [renamePrimaryOpen, setRenamePrimaryOpen] = useState(false);
   const [routeTarget, setRouteTarget] = useState<EnvironmentPresentation | null>(null);
   const [savedBackendError, setSavedBackendError] = useState<string | null>(null);
   const handleAddBackendDialogOpenChange = (open: boolean) => {
@@ -1046,26 +1048,39 @@ export function ConnectionsSettings() {
             }
             headerAction={
               primaryEnvironmentId !== null ? (
-                <Menu>
-                  <MenuTrigger
-                    render={
-                      <Button
-                        type="button"
-                        variant="ghost-muted"
-                        size="icon-xs"
-                        aria-label="More actions for this machine"
+                <>
+                  <Menu>
+                    <MenuTrigger
+                      render={
+                        <Button
+                          type="button"
+                          variant="ghost-muted"
+                          size="icon-xs"
+                          aria-label="More actions for this machine"
+                        />
+                      }
+                    >
+                      <EllipsisIcon className="size-3.5" />
+                    </MenuTrigger>
+                    <MenuPopup align="end">
+                      <EnvironmentIconMenu
+                        environmentId={primaryEnvironmentId}
+                        serverConfig={primaryServerConfig}
                       />
-                    }
-                  >
-                    <EllipsisIcon className="size-3.5" />
-                  </MenuTrigger>
-                  <MenuPopup align="end">
-                    <EnvironmentIconMenu
-                      environmentId={primaryEnvironmentId}
-                      serverConfig={primaryServerConfig}
-                    />
-                  </MenuPopup>
-                </Menu>
+                      <MenuItem onClick={() => setRenamePrimaryOpen(true)}>
+                        <PencilIcon />
+                        Rename…
+                      </MenuItem>
+                    </MenuPopup>
+                  </Menu>
+                  <EnvironmentRenameDialog
+                    environmentId={primaryEnvironmentId}
+                    serverConfig={primaryServerConfig}
+                    label={primaryEnvironment?.label ?? ""}
+                    open={renamePrimaryOpen}
+                    onOpenChange={setRenamePrimaryOpen}
+                  />
+                </>
               ) : null
             }
           >
diff --git a/apps/web/src/components/settings/EnvironmentRenameDialog.tsx b/apps/web/src/components/settings/EnvironmentRenameDialog.tsx
new file mode 100644
index 0000000000000..5038d7ec62d70
--- /dev/null
+++ b/apps/web/src/components/settings/EnvironmentRenameDialog.tsx
@@ -0,0 +1,144 @@
+import { AuthSettingsWriteScope, type EnvironmentId, type ServerConfig } from "@t3tools/contracts";
+import { useState } from "react";
+
+import { useUpdateEnvironmentSettings } from "../../hooks/useSettings";
+import { useEnvironmentScope } from "../../state/session";
+import { Button } from "../ui/button";
+import {
+  Dialog,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogPanel,
+  DialogPopup,
+  DialogTitle,
+} from "../ui/dialog";
+import { Input } from "../ui/input";
+
+type RenameServerConfig = Pick<ServerConfig, "environment" | "settings"> | null;
+
+function resolveEnvironmentRenameLock(input: {
+  readonly serverConfig: Pick<ServerConfig, "environment"> | null;
+  readonly operateAccess: "granted" | "denied" | "pending";
+}): string | null {
+  if (input.serverConfig === null) {
+    return "Connect to this environment to rename it.";
+  }
+  if (input.serverConfig.environment.capabilities.environmentLabel !== true) {
+    return "This environment's server is too old to keep a name. Update it to rename it.";
+  }
+  if (input.operateAccess !== "granted") {
+    return "Your session on this environment cannot change its settings.";
+  }
+  return null;
+}
+
+export function EnvironmentRenameDialog({
+  environmentId,
+  serverConfig,
+  label,
+  open,
+  onOpenChange,
+}: {
+  readonly environmentId: EnvironmentId;
+  readonly serverConfig: RenameServerConfig;
+  readonly label: string;
+  readonly open: boolean;
+  readonly onOpenChange: (open: boolean) => void;
+}) {
+  return (
+    <Dialog open={open} onOpenChange={onOpenChange}>
+      <DialogPopup className="max-w-md">
+        <EnvironmentRenameForm
+          key={open ? "open" : "closed"}
+          environmentId={environmentId}
+          serverConfig={serverConfig}
+          label={label}
+          onClose={() => onOpenChange(false)}
+        />
+      </DialogPopup>
+    </Dialog>
+  );
+}
+
+function EnvironmentRenameForm({
+  environmentId,
+  serverConfig,
+  label,
+  onClose,
+}: {
+  readonly environmentId: EnvironmentId;
+  readonly serverConfig: RenameServerConfig;
+  readonly label: string;
+  readonly onClose: () => void;
+}) {
+  const updateSettings = useUpdateEnvironmentSettings(environmentId);
+  const operateAccess = useEnvironmentScope(environmentId, AuthSettingsWriteScope)
+    ? "granted"
+    : "denied";
+  const lock = resolveEnvironmentRenameLock({ serverConfig, operateAccess });
+  const customLabel = serverConfig?.settings?.environmentLabel ?? null;
+  const [name, setName] = useState(label);
+
+  const save = (environmentLabel: string | null) => {
+    if (lock !== null) return;
+    if (environmentLabel !== customLabel) {
+      updateSettings({ environmentLabel });
+    }
+    onClose();
+  };
+  const submit = () => {
+    const trimmed = name.trim();
+    save(trimmed === "" || (customLabel === null && trimmed === label) ? null : trimmed);
+  };
+
+  return (
+    <form
+      className="flex min-h-0 flex-col"
+      onSubmit={(event) => {
+        event.preventDefault();
+        submit();
+      }}
+    >
+      <DialogHeader>
+        <DialogTitle>Rename environment</DialogTitle>
+        <DialogDescription>
+          Every client connected to this environment shows this name. Leave it empty to use the
+          default name.
+        </DialogDescription>
+      </DialogHeader>
+      <DialogPanel>
+        <div className="grid gap-1.5">
+          <span className="text-xs font-medium text-foreground">Name</span>
+          <Input
+            aria-label="Environment name"
+            disabled={lock !== null}
+            maxLength={64}
+            value={name}
+            onChange={(event) => setName(event.target.value)}
+          />
+        </div>
+        {lock !== null ? <p className="text-xs text-muted-foreground">{lock}</p> : null}
+      </DialogPanel>
+      <DialogFooter>
+        {customLabel !== null ? (
+          <Button
+            type="button"
+            variant="ghost"
+            className="sm:mr-auto"
+            disabled={lock !== null}
+            onClick={() => save(null)}
+          >
+            Use default name
+          </Button>
+        ) : null}
+        <Button type="button" variant="outline" onClick={onClose}>
+          Cancel
+        </Button>
+        <Button type="submit" disabled={lock !== null}>
+          Save
+        </Button>
+      </DialogFooter>
+    </form>
+  );
+}
diff --git a/apps/web/src/components/settings/SavedEnvironmentRows.tsx b/apps/web/src/components/settings/SavedEnvironmentRows.tsx
index 5a331193bcae0..b0922557025fb 100644
--- a/apps/web/src/components/settings/SavedEnvironmentRows.tsx
+++ b/apps/web/src/components/settings/SavedEnvironmentRows.tsx
@@ -3,6 +3,7 @@ import {
   ChevronRightIcon,
   ChevronsLeftRightEllipsisIcon,
   EllipsisIcon,
+  PencilIcon,
   RouteIcon,
 } from "lucide-react";
 import { useAtomValue } from "@effect/atom-react";
@@ -27,6 +28,7 @@ import { cn } from "../../lib/utils";
 import { SettingsRow } from "./settingsLayout";
 import { searchableSetting } from "./settingsSearch";
 import { EnvironmentIconMenu } from "./EnvironmentIconPicker";
+import { EnvironmentRenameDialog } from "./EnvironmentRenameDialog";
 import { EnvironmentRoutesList } from "./EnvironmentRoutesList";
 import {
   ConnectionDiagnosisPanel,
@@ -115,6 +117,7 @@ export function SavedBackendListRow({
   onAddRoute,
 }: SavedBackendListRowProps) {
   const [routesOpen, setRoutesOpen] = useState(false);
+  const [renameOpen, setRenameOpen] = useState(false);
   const [permissionsOpen, setPermissionsOpen] = useState(false);
   const [diagnosisOpen, setDiagnosisOpen] = useState(false);
   const environmentId = environment.environmentId;
@@ -414,6 +417,10 @@ export function SavedBackendListRow({
             environmentId={environmentId}
             serverConfig={environment.serverConfig}
           />
+          <MenuItem onClick={() => setRenameOpen(true)}>
+            <PencilIcon />
+            Rename…
+          </MenuItem>
           <MenuItem onClick={() => setRoutesOpen((open) => !open)}>
             <RouteIcon />
             {routesOpen ? "Hide routes" : "Routes"}
@@ -430,6 +437,13 @@ export function SavedBackendListRow({
           </MenuItem>
         </MenuPopup>
       </Menu>
+      <EnvironmentRenameDialog
+        environmentId={environmentId}
+        serverConfig={environment.serverConfig}
+        label={environment.label}
+        open={renameOpen}
+        onOpenChange={setRenameOpen}
+      />
     </EnvironmentRow>
   );
 }
diff --git a/apps/web/src/components/usage/UsagePriceOverrides.tsx b/apps/web/src/components/usage/UsagePriceOverrides.tsx
index efa0f4535338f..2d6aa96a45c70 100644
--- a/apps/web/src/components/usage/UsagePriceOverrides.tsx
+++ b/apps/web/src/components/usage/UsagePriceOverrides.tsx
@@ -59,7 +59,7 @@ const priceTargetsAtom = Atom.make((get): readonly UsagePriceTarget[] =>
             : "denied";
     return {
       environmentId,
-      label: environment.entry.target.label,
+      label: environment.label,
       prices: settings?.usagePriceOverrides ?? null,
       aliases:
         environment.serverConfig?.environment.capabilities.usageModelAliases === true
diff --git a/apps/web/src/state/environments.ts b/apps/web/src/state/environments.ts
index e399c201c34d8..0b2c2b5a11998 100644
--- a/apps/web/src/state/environments.ts
+++ b/apps/web/src/state/environments.ts
@@ -21,7 +21,6 @@ import { usePreparedConnection } from "./session";
 
 export interface EnvironmentPresentation extends BaseEnvironmentPresentation {
   readonly environmentId: EnvironmentId;
-  readonly label: string;
   readonly displayUrl: string | null;
   readonly relayManaged: boolean;
 }
@@ -33,7 +32,6 @@ function projectEnvironmentPresentation(
   return {
     ...presentation,
     environmentId,
-    label: presentation.entry.target.label,
     displayUrl: connectionCatalogDisplayUrl(presentation.entry),
     relayManaged: hasRelayRoute(presentation.entry),
   };
diff --git a/apps/web/src/state/usage.ts b/apps/web/src/state/usage.ts
index a5bb95c430c8b..38f0e3637ed69 100644
--- a/apps/web/src/state/usage.ts
+++ b/apps/web/src/state/usage.ts
@@ -48,7 +48,7 @@ const usageByWindowAtom = Atom.family((windowKey: string) =>
       if (!access.canReadDiagnostics) {
         statuses.push({
           environmentId,
-          label: presentation.entry.target.label,
+          label: presentation.label,
           isConnected,
           ...access,
           summary: null,
@@ -60,7 +60,7 @@ const usageByWindowAtom = Atom.family((windowKey: string) =>
       const summary = Option.getOrNull(AsyncResult.value(result));
       statuses.push({
         environmentId,
-        label: presentation.entry.target.label,
+        label: presentation.label,
         isPending: result.waiting,
         canReadDiagnostics: true,
         isConnected,
diff --git a/docs/user/remote-access.md b/docs/user/remote-access.md
index fbda09d6af41d..a5467b1fc7fb8 100644
--- a/docs/user/remote-access.md
+++ b/docs/user/remote-access.md
@@ -104,6 +104,14 @@ shown there apply only to the route marked **In use**; other routes are not
 checked. Direct pairing and T3 Connect have separate sessions and may grant
 different permissions.
 
+### Name a machine
+
+An environment is named after its machine, so two user accounts on one computer
+show the same name. To tell them apart, open the environment's menu in
+**Settings → Connections** and choose **Rename…**. The name is saved on that
+environment, so every connected device shows it. Clear the name to go back to
+the default.
+
 ### Balance new threads across machines
 
 Auto balance is off by default. On web and desktop, enable it in
diff --git a/packages/client-runtime/src/connection/presentation.ts b/packages/client-runtime/src/connection/presentation.ts
index 6bfa9791dfdca..73770528d623b 100644
--- a/packages/client-runtime/src/connection/presentation.ts
+++ b/packages/client-runtime/src/connection/presentation.ts
@@ -29,6 +29,7 @@ export type EnvironmentServerConfig = Omit<ServerConfig, "providers">;
 
 export interface EnvironmentPresentation {
   readonly entry: ConnectionCatalogEntry;
+  readonly label: string;
   readonly connection: EnvironmentConnectionPresentation;
   readonly serverConfig: EnvironmentServerConfig | null;
 }
diff --git a/packages/client-runtime/src/state/presentation.test.ts b/packages/client-runtime/src/state/presentation.test.ts
index 3c3fa20a4a976..28adc869a94f8 100644
--- a/packages/client-runtime/src/state/presentation.test.ts
+++ b/packages/client-runtime/src/state/presentation.test.ts
@@ -88,6 +88,29 @@ describe("environment summary subscriptions", () => {
       h.registry.dispose();
     }
   });
+
+  it("labels an environment by its custom name until the name is cleared", () => {
+    const h = harness();
+    const named = (environmentLabel: string | null) =>
+      ({ ...config(), settings: { environmentLabel } }) as ServerConfig;
+    const stop = h.registry.subscribe(h.identitiesAtom, () => {});
+    try {
+      h.registry.set(h.configs(FIRST), named("MacBook Pro · user2"));
+      expect(h.registry.get(h.full.presentationAtom(FIRST))?.label).toBe("MacBook Pro · user2");
+      expect(h.registry.get(h.identitiesAtom)).toEqual([
+        { environmentId: FIRST, label: "MacBook Pro · user2" },
+        { environmentId: SECOND, label: "second" },
+      ]);
+      expect(h.registry.get(h.environmentsAtom)[0]?.environmentLabel).toBe("MacBook Pro · user2");
+
+      h.registry.set(h.configs(FIRST), named(null));
+      expect(h.registry.get(h.full.presentationAtom(FIRST))?.label).toBe("first");
+      expect(h.registry.get(h.identitiesAtom)[0]).toEqual({ environmentId: FIRST, label: "first" });
+    } finally {
+      stop();
+      h.registry.dispose();
+    }
+  });
 });
 
 describe("presentations with providers", () => {
diff --git a/packages/client-runtime/src/state/presentation.ts b/packages/client-runtime/src/state/presentation.ts
index 48d27974a2c8c..c43b153c0d247 100644
--- a/packages/client-runtime/src/state/presentation.ts
+++ b/packages/client-runtime/src/state/presentation.ts
@@ -1,4 +1,5 @@
 import {
+  resolveEnvironmentLabel,
   resolveEnvironmentMachineKind,
   type EnvironmentMachineKind,
   type EnvironmentId,
@@ -86,19 +87,22 @@ export function createEnvironmentPresentationAtoms<E>(input: {
         entry.unsupportedReason === undefined
           ? presentEnvironmentConnection(state)
           : { phase: "unsupported", error: entry.unsupportedReason, traceId: null };
+      const serverConfig = withoutProviders(
+        get(input.serverConfigValueAtom(environmentId)),
+        previous?.serverConfig ?? null,
+      );
       const next = {
         entry,
+        label: resolveEnvironmentLabel(serverConfig, entry.target.label),
         connection:
           previous !== null && sameConnection(previous.connection, connection)
             ? previous.connection
             : connection,
-        serverConfig: withoutProviders(
-          get(input.serverConfigValueAtom(environmentId)),
-          previous?.serverConfig ?? null,
-        ),
+        serverConfig,
       } satisfies EnvironmentPresentation;
       return previous !== null &&
         previous.entry === next.entry &&
+        previous.label === next.label &&
         previous.connection === next.connection &&
         previous.serverConfig === next.serverConfig
         ? previous
@@ -204,7 +208,7 @@ export function projectEnvironmentConnectionSummary(
 ): EnvironmentConnectionSummary {
   return {
     environmentId,
-    environmentLabel: environment.entry.target.label,
+    environmentLabel: environment.label,
     displayUrl: connectionCatalogDisplayUrl(environment.entry) ?? "",
     isRelayManaged: hasRelayRoute(environment.entry),
     isEnabled: environment.entry.enabled,
@@ -232,7 +236,7 @@ export function createEnvironmentSummaryAtoms(input: {
   const identitiesAtom = Atom.make((get) => {
     const next = [...get(input.catalogValueAtom).entries].map(([environmentId, entry]) => ({
       environmentId,
-      label: entry.target.label,
+      label: get(input.presentationAtom(environmentId))?.label ?? entry.target.label,
     }));
     const previous = Option.getOrNull(
       get.self<ReadonlyArray<{ readonly environmentId: EnvironmentId; readonly label: string }>>(),
diff --git a/packages/contracts/src/environment.ts b/packages/contracts/src/environment.ts
index 7b47d88202c7d..bd47125cc7e0f 100644
--- a/packages/contracts/src/environment.ts
+++ b/packages/contracts/src/environment.ts
@@ -129,6 +129,7 @@ export const ExecutionEnvironmentCapabilities = Schema.Struct({
   /** Server answers projects.listIgnoredFiles. */
   ignoredFileListing: Schema.optionalKey(Schema.Boolean),
   environmentIcon: Schema.optionalKey(Schema.Boolean),
+  environmentLabel: Schema.optionalKey(Schema.Boolean),
   desktopAppUpdate: Schema.optionalKey(Schema.Boolean),
   /** Subscribe to command output only when advertised; older servers never send it. */
   commandOutputStreaming: Schema.optionalKey(Schema.Boolean),
diff --git a/packages/contracts/src/server.ts b/packages/contracts/src/server.ts
index c14b4b4b24eaf..bbc721b0df5f7 100644
--- a/packages/contracts/src/server.ts
+++ b/packages/contracts/src/server.ts
@@ -640,6 +640,14 @@ export function resolveEnvironmentMachineKind(
   return config?.settings?.environmentIcon ?? config?.environment.platform.machine ?? "server";
 }
 
+/** A custom label wins over the label the client saved when it added the environment. */
+export function resolveEnvironmentLabel(
+  config: { readonly settings?: Pick<ServerSettings, "environmentLabel"> } | null,
+  savedLabel: string,
+): string {
+  return config?.settings?.environmentLabel ?? savedLabel;
+}
+
 const ServerUpsertKeybindingReplaceTarget = Schema.Struct({
   key: KeybindingValue,
   command: KeybindingCommand,
diff --git a/packages/contracts/src/settings.ts b/packages/contracts/src/settings.ts
index 88460d06bcdf6..4903a6fa00b3e 100644
--- a/packages/contracts/src/settings.ts
+++ b/packages/contracts/src/settings.ts
@@ -245,6 +245,8 @@ export const FontFamilyPreference = Schema.String.check(Schema.isMaxLength(200))
 export type FontFamilyPreference = typeof FontFamilyPreference.Type;
 
 /** Clients apply each environment theme set once; later local choices persist until the next set. Empty clears it. */
+export const EnvironmentLabel = TrimmedNonEmptyString.check(Schema.isMaxLength(64));
+
 export const DefaultThemePreference = Schema.String.check(Schema.isMaxLength(64));
 // Excluded from RPC patches so t3 theme set can validate syntax and resolvability.
 export type DefaultThemePreference = typeof DefaultThemePreference.Type;
@@ -1195,6 +1197,10 @@ export const ServerSettings = Schema.Struct({
   environmentIcon: ForwardCompatibleNullable(EnvironmentMachineKind).pipe(
     Schema.withDecodingDefault(Effect.succeed(null)),
   ),
+  /** Null keeps the detected machine name. */
+  environmentLabel: Schema.NullOr(EnvironmentLabel).pipe(
+    Schema.withDecodingDefault(Effect.succeed(null)),
+  ),
   /** Null inherits t3.json, then local; omit it on the wire for older clients requiring a literal. */
   defaultThreadEnvMode: OmittedWhenNull(ThreadEnvMode),
   newWorktreesStartFromOrigin: Schema.Boolean.pipe(
@@ -1525,6 +1531,7 @@ export const ServerSettingsPatch = Schema.Struct({
   providerHealthRefreshInterval: Schema.optionalKey(Schema.DurationFromMillis),
   backgroundActivityProfile: Schema.optionalKey(BackgroundActivityProfile),
   environmentIcon: Schema.optionalKey(Schema.NullOr(EnvironmentMachineKind)),
+  environmentLabel: Schema.optionalKey(Schema.NullOr(EnvironmentLabel)),
   defaultThreadEnvMode: Schema.optionalKey(Schema.NullOr(ThreadEnvMode)),
   newWorktreesStartFromOrigin: Schema.optionalKey(Schema.Boolean),
   worktreeSubmodules: Schema.optionalKey(Schema.NullOr(WorktreeSubmodules)),