diff --git a/apps/docs/docs/management/api/index.mdx b/apps/docs/docs/management/api/index.mdx
index c975f9a9f..c89882c3e 100644
--- a/apps/docs/docs/management/api/index.mdx
+++ b/apps/docs/docs/management/api/index.mdx
@@ -27,6 +27,12 @@ session cookie.
 API keys do not expire automatically and act as the user that created them. Every request uses that user's group and
 resource permissions.
 
+## Invitation dates
+
+`POST /api/invites` and the tRPC `invite.createInvite` procedure accept `expirationDate` as an ISO 8601 timestamp with a
+timezone, for example `2026-12-01T18:00:00Z`. Homarr validates the timestamp and stores it as a date. tRPC callers should
+send the ISO string rather than a JavaScript `Date` object.
+
 ## Health probes
 
 The liveness endpoint does not require authentication:
diff --git a/apps/docs/docs/management/mcp.mdx b/apps/docs/docs/management/mcp.mdx
index 39f7f2229..3a37ce9da 100644
--- a/apps/docs/docs/management/mcp.mdx
+++ b/apps/docs/docs/management/mcp.mdx
@@ -55,6 +55,9 @@ the catalog by namespace, tool name, or description; matching categories expand
 MCP supports API keys and OAuth 2.1 with PKCE. API keys are simpler for direct client configuration; OAuth is available
 for clients that support dynamic authorization.
 
+Copy the complete generated API key, including both parts and the dot: `<id>.<token>`. Sending only the ID or token
+returns `invalid_token`. Keep the full key private when sharing client configuration or diagnostics.
+
 When Homarr is behind a reverse proxy that does not preserve the public host and protocol, set `BASE_URL` to the exact
 public origin, for example `https://homarr.example.com`. Do not include a path. OAuth clients discover the authorization
 server and protected resource through Homarr's `/.well-known/` routes.
@@ -79,12 +82,20 @@ curl -X POST \
 
 The removed HTTP+SSE `/sse` and `/message` transports return `410 Gone`.
 
+Successful `server/discover` or `initialize` responses confirm connectivity, but do not validate the tool catalog.
+Use `tools/list` above to check that the client can discover tools. If it returns
+`Date cannot be represented in JSON Schema`, the server failed to generate a tool schema; changing the API key will
+not resolve that error. Update Homarr to a release containing the invitation date schema fix.
+
 ## Tools and resources
 
 The generated catalog includes available board, app, integration, Docker, Kubernetes, media, DNS, download, and other
 Homarr procedures. Queries are read-only; mutations change state. The exact catalog depends on the release and current
 user permissions, so inspect `tools/list` or the table in Homarr instead of relying on a static list.
 
+The `invite_createInvite` tool accepts `expirationDate` as an ISO 8601 timestamp with a timezone, such as
+`2026-12-01T18:00:00Z` or `2026-12-01T19:00:00+01:00`.
+
 For Custom Widgets, install the official skill and follow the preview-and-evidence workflow described in
 [Connect an agent](./custom-widgets/agent-authoring). Secret values are configured in Homarr and are never returned
 through MCP.
diff --git a/apps/docs/static/api/open-api-schema.json b/apps/docs/static/api/open-api-schema.json
index 8a3df7032..847c90fe6 100644
--- a/apps/docs/static/api/open-api-schema.json
+++ b/apps/docs/static/api/open-api-schema.json
@@ -2572,7 +2572,9 @@
                 "type": "object",
                 "properties": {
                   "expirationDate": {
-                    "type": "string"
+                    "type": "string",
+                    "format": "date-time",
+                    "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d(?::[0-5]\\d(?:\\.\\d+)?)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"
                   }
                 },
                 "required": [
diff --git a/apps/nextjs/src/app/[locale]/manage/users/invites/_components/invite-create-form.tsx b/apps/nextjs/src/app/[locale]/manage/users/invites/_components/invite-create-form.tsx
index c56aecf0b..8b2b88dc5 100644
--- a/apps/nextjs/src/app/[locale]/manage/users/invites/_components/invite-create-form.tsx
+++ b/apps/nextjs/src/app/[locale]/manage/users/invites/_components/invite-create-form.tsx
@@ -45,7 +45,7 @@ export const InviteCreateForm = ({ onClose }: InviteCreateFormProps) => {
       onSubmit={form.onSubmit((values) => {
         mutate(
           {
-            expirationDate: new Date(values.expirationDate),
+            expirationDate: new Date(values.expirationDate).toISOString(),
           },
           {
             onSuccess: (result) => {
diff --git a/packages/api/src/mcp-tools.ts b/packages/api/src/mcp-tools.ts
index d9ade36a0..ecfd06a4b 100644
--- a/packages/api/src/mcp-tools.ts
+++ b/packages/api/src/mcp-tools.ts
@@ -109,6 +109,7 @@ export function extractMcpToolsFromProcedures<TRoot extends AnyRootTypes, TRecor
       inputValidator,
       inputSchema: normalizeJsonSchema(
         z.toJSONSchema(inputValidator, {
+          io: "input",
           unrepresentable: "any",
         }),
       ),
diff --git a/packages/api/src/router/invite.ts b/packages/api/src/router/invite.ts
index bc31c0bdf..e56621d7a 100644
--- a/packages/api/src/router/invite.ts
+++ b/packages/api/src/router/invite.ts
@@ -56,7 +56,7 @@ export const inviteRouter = createTRPCRouter({
     .requiresPermission("admin")
     .input(
       z.object({
-        expirationDate: z.date(),
+        expirationDate: z.iso.datetime({ offset: true }),
       }),
     )
     .output(z.object({ id: z.string(), token: z.string() }))
@@ -80,7 +80,7 @@ export const inviteRouter = createTRPCRouter({
 
       await ctx.db.insert(invites).values({
         id,
-        expirationDate: input.expirationDate,
+        expirationDate: new Date(input.expirationDate),
         creatorId: ctx.session.user.id,
         token,
       });
diff --git a/packages/api/src/router/test/invite.spec.ts b/packages/api/src/router/test/invite.spec.ts
index 57a157de3..05fa4f55b 100644
--- a/packages/api/src/router/test/invite.spec.ts
+++ b/packages/api/src/router/test/invite.spec.ts
@@ -123,7 +123,7 @@ describe("create should create a new invite expiring on the specified date with
 
     // Act
     const result = await caller.createInvite({
-      expirationDate,
+      expirationDate: expirationDate.toISOString(),
     });
 
     // Assert