fix: require attach before resize

docs/vrs/requirements.md

@@ -21,8 +21,9 @@ implementation contract and validation map live in [spec.md](./spec.md).
 
 - **T01 Per-session daemon:** Each session pays for an independent daemon in
   exchange for client-independent lifetime and failure isolation.
-- **T02 Shared grid:** All writable clients share the minimum requested rows and
-  minimum requested columns so every writer can represent the complete grid.
+- **T02 Shared grid:** All writable-attached clients share the minimum requested
+  rows and minimum requested columns so every attached writer can represent the
+  complete grid.
 - **T03 Pre-1.0 compatibility:** Public storage and package APIs may evolve
   before 1.0, but readers remain bounded and documented compatibility tiers are
   preserved deliberately.
@@ -56,12 +57,15 @@ implementation contract and validation map live in [spec.md](./spec.md).
   emits terminal state sends effective geometry, exactly one screen baseline,
   then post-cut data and at most one process exit in source order. A later mode
   request supersedes an unfinished generation; reconnect starts a new one.
-- **R05 Replaceable client roles:** A complete `ATTACH` makes its socket
-  writable, installs requested geometry, and enables input and resize. A
-  recognized `PEEK` makes it readonly and removes its geometry constraint. A
-  malformed attach changes neither role nor synchronization generation.
+- **R05 Replaceable client roles:** A fresh command socket accepts input and
+  status requests but starts no screen baseline, has no geometry membership,
+  and cannot resize. A complete `ATTACH` makes it writable-attached, retaining
+  input and status capabilities while installing requested geometry, enabling
+  resize, and starting ordered baseline synchronization. A recognized `PEEK`
+  makes it readonly and removes its geometry constraint. A malformed attach
+  changes neither role nor synchronization generation.
 - **R06 Deterministic geometry:** Effective rows and columns are the independent
-  minima requested by writable clients. Attach, resize, and disconnect
+  minima requested by writable-attached clients. Attach, resize, and disconnect
   recompute them; readonly observation never constrains them. Geometry changes
   are visible before terminal bytes produced for the new size.
 - **R07 Bounded stream protocol:** Packets are length-delimited, fragmented

docs/vrs/spec.md

@@ -96,16 +96,32 @@ A local machine detach may end with `DETACH` before a baseline is emitted.
 
 ### Roles and geometry
 
-Role frames replace, rather than accumulate, socket state (R05):
+Each socket begins in the command role. Role frames replace, rather than
+accumulate, socket state (R05):
 
 | Frame | Resulting role | Geometry membership | Input/resize |
 | --- | --- | --- | --- |
-| complete `ATTACH(rows, cols)` | writable | requested rows/cols | enabled |
+| complete `ATTACH(rows, cols)` | writable-attached | requested rows/cols | enabled |
 | recognized `PEEK(flags)` | readonly | none | disabled |
 | malformed `ATTACH` | unchanged | unchanged | unchanged |
 | `STATUS` | unchanged | unchanged | unchanged |
 
-For writable request set `W`, shared geometry is (R06):
+Client-to-server data, status, and resize behavior is role-specific:
+
+| Role | `DATA` | `STATUS` | `RESIZE` |
+| --- | --- | --- | --- |
+| command | accepted | accepted | ignored |
+| writable-attached | accepted | accepted | accepted |
+| readonly | ignored | accepted | ignored |
+
+Command sockets do not receive a screen baseline and do not participate in
+geometry. They may receive baseline-less live `DATA` or `EXIT` broadcasts;
+those packets do not constitute reconstructable terminal state. A consumer that
+needs reconstructable terminal state must first send `ATTACH` or `PEEK`. Public
+stats omit command sockets and expose the writable-attached role with the
+compatibility string `"writable"`.
+
+For writable-attached request set `W`, shared geometry is (R06):
 
 ```text
 rows = min(client.rows for client in W)
@@ -114,7 +130,7 @@ cols = min(client.cols for client in W)
 
 The dimensions are minimized independently. A changed `GEOMETRY` notification
 precedes terminal output produced after the corresponding PTY resize. Removing
-the last writable client leaves the last effective geometry stable.
+the last writable-attached client leaves the last effective geometry stable.
 
 ### Machine attach
 

src/server.ts

@@ -1021,7 +1021,7 @@ export class PtyServer {
           }
 
           case MessageType.RESIZE: {
-            if (!client.readonly && packet.payload.length >= 4) {
+            if (!client.readonly && client.attachSeq > 0 && packet.payload.length >= 4) {
               const size = decodeSize(packet.payload);
               client.rows = size.rows;
               client.cols = size.cols;

tests/integration.test.ts

@@ -2063,6 +2063,58 @@ describe("STATUS message", () => {
     statsClient.destroy();
   });
 
+  it("ignores RESIZE from a command socket until that socket attaches", async () => {
+    const name = uniqueName();
+    await startServer(name, "cat");
+
+    const attached = await connect(name);
+    const attachedPackets = recordPackets(attached);
+    attached.write(encodeAttach(24, 80));
+    await attachedPackets.waitFor((packets) =>
+      packets.some((packet) => packet.type === MessageType.SCREEN)
+    );
+
+    const command = await connect(name);
+    const commandPackets = recordPackets(command);
+    command.write(
+      Buffer.concat([
+        encodeData("command-input-remains-valid\n"),
+        encodeResize(13, 37),
+        encodeStatus(),
+      ])
+    );
+    await commandPackets.waitFor((packets) =>
+      packets.some((packet) => packet.type === MessageType.STATUS)
+    );
+    await attachedPackets.waitFor((packets) =>
+      packets.some(
+        (packet) =>
+          packet.type === MessageType.DATA &&
+          packet.payload.toString().includes("command-input-remains-valid")
+      )
+    );
+
+    const status = commandPackets.packets.find(
+      (packet) => packet.type === MessageType.STATUS
+    )!;
+    const stats = JSON.parse(status.payload.toString());
+    expect(stats.clients).toMatchObject({
+      total: 1,
+      attached: 1,
+      readOnly: 0,
+    });
+    expect(stats.terminal).toMatchObject({ rows: 24, cols: 80 });
+    expect(
+      commandPackets.packets.some((packet) => packet.type === MessageType.GEOMETRY)
+    ).toBe(false);
+    expect(
+      commandPackets.packets.some((packet) => packet.type === MessageType.SCREEN)
+    ).toBe(false);
+
+    attached.destroy();
+    command.destroy();
+  });
+
   it("reports anonymous client geometry and per-axis constraints", async () => {
     const name = uniqueName();
     await startServer(name, "cat");