fix(coding-agent): scope disabled-only autocomplete to enable/disable; fix changelog section

- collectMcpServerNames takes an includeDisabled flag (default true); the
  /mcp completer now passes false for test/reconnect/reauth/unauth, whose
  handlers (#resolveServerForAuth, reconnectServer) can never resolve a
  disabled-only discovered name (dropped from mcpManager, absent from
  mcpServers). enable/disable keep offering it since #handleSetEnabled
  handles that case for both directions.
- Moved the /mcp autocomplete CHANGELOG entry from the now-released
  ## [17.1.0] section (where an earlier upstream merge relocated it) back
  under ## [Unreleased].

packages/coding-agent/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Added
+
+- Added server-name autocomplete for `/mcp enable`, `disable`, `test`, `remove`, `reconnect`, `reauth`, and `unauth`, sourced from configured and runtime-discovered MCP servers ([#5654](https://github.com/can1357/oh-my-pi/issues/5654)).
+
 ## [17.1.0] - 2026-07-24
 
 ### Breaking Changes
@@ -23,7 +27,6 @@
 - Added a toggle-list editor in `/settings` for managing array-of-enum settings like search and image provider orders.
 - Added `models.yml` Bedrock Converse prompt-cache capability overrides for bundled and opaque inference profiles.
 - Documented Vibe mode (`/vibe`) in `docs/vibe-mode.md` and the `/fresh` provider-stream reset in the session-operations doc, and linked both from the README's new "Session controls" section ([#6440](https://github.com/can1357/oh-my-pi/issues/6440)).
-- Added server-name autocomplete for `/mcp enable`, `disable`, `test`, `remove`, `reconnect`, `reauth`, and `unauth`, sourced from configured and runtime-discovered MCP servers ([#5654](https://github.com/can1357/oh-my-pi/issues/5654)).
 - Added `getServiceTiers()` and `setServiceTier()` extension APIs for reading and changing the live per-family service tier used by subsequent session requests ([#5860](https://github.com/can1357/oh-my-pi/issues/5860)).
 - Added opt-in `omp bench --cache` independent cold/warm prompt-cache pairs with stable-prefix controls, sequential-by-default execution, mechanism-specific provider proof, and privacy-safe JSON output; it rejects `openai-codex-responses`, whose WebSocket transport chains turns.
 - Added `tools.xdevDocs` prompt-doc modes (`inline`, `builtins`, `catalog`) and the `tools.xdevInlineDevices` glob allowlist controlling which mounted `xd://` device docs are inlined into the system prompt; dynamic-device catalog summaries and mid-session mount notices are capped to one line, and changing the mode in `/settings` refreshes the active prompt ([#6063](https://github.com/can1357/oh-my-pi/issues/6063)).

packages/coding-agent/src/modes/controllers/mcp-command-controller.ts

@@ -254,16 +254,21 @@ type MCPSearchParsed = {
 
 /**
  * Collect the de-duplicated union of every MCP server name we know about:
- * user config, project config, disabled-server entries, and any
- * runtime-discovered servers not already present in either config
- * (`ctx.mcpManager.getAllServerNames()` covers connections, pending
- * connections, and discovered-but-not-yet-connected sources). Disabled
- * servers stay in this list — disabling a server only flips its config
- * `enabled` flag, it doesn't remove the config entry, so a disabled server
- * is still a valid `/mcp enable <name>` target. This also covers a
- * discovered (non-config) server that was disabled: `loadAllMCPConfigs`
- * filters it out of `getAllServerNames()`, but its name survives in
- * `userConfig.disabledServers`.
+ * user config, project config, and any runtime-discovered servers not
+ * already present in either config (`ctx.mcpManager.getAllServerNames()`
+ * covers connections, pending connections, and discovered-but-not-yet-
+ * connected sources).
+ *
+ * When `includeDisabled` is true (the default), disabled-server entries
+ * are unioned in too — disabling a server only flips its config `enabled`
+ * flag, it doesn't remove the config entry, so a disabled server is still
+ * a valid `/mcp enable <name>` target. This also covers a discovered
+ * (non-config) server that was disabled: `loadAllMCPConfigs` filters it
+ * out of `getAllServerNames()`, but its name survives in
+ * `userConfig.disabledServers`. Callers whose target operation needs a
+ * live connection or config entry (`/mcp test`/`reconnect`/`reauth`/
+ * `unauth`) — which a disabled-only name can never satisfy — must pass
+ * `includeDisabled: false`.
  *
  * This is the single source of truth for "every known server name": both
  * `MCPCommandController#handleList()` and the `/mcp` slash-command argument
@@ -276,6 +281,7 @@ type MCPSearchParsed = {
 export async function collectMcpServerNames(
 	ctx: InteractiveModeContext,
 	preloaded?: { userConfig: MCPConfigFile; projectConfig: MCPConfigFile },
+	includeDisabled = true,
 ): Promise<string[]> {
 	let userConfig: MCPConfigFile;
 	let projectConfig: MCPConfigFile;
@@ -292,7 +298,7 @@ export async function collectMcpServerNames(
 	const names = new Set<string>([
 		...Object.keys(userConfig.mcpServers ?? {}),
 		...Object.keys(projectConfig.mcpServers ?? {}),
-		...(userConfig.disabledServers ?? []),
+		...(includeDisabled ? (userConfig.disabledServers ?? []) : []),
 	]);
 	if (ctx.mcpManager) {
 		for (const name of ctx.mcpManager.getAllServerNames()) {

packages/coding-agent/src/slash-commands/builtin-registry.ts

@@ -2457,6 +2457,18 @@ const MCP_SERVER_NAME_SUBCOMMANDS: ReadonlySet<string> = new Set([
 	"unauth",
 ]);
 
+/**
+ * `/mcp` subcommands where a discovered server disabled via `/mcp disable`
+ * (name only in `userConfig.disabledServers`, dropped from
+ * `mcpManager.getAllServerNames()` by `loadAllMCPConfigs`) is still a valid
+ * completion target: `enable` is the primary re-enable path, and offering
+ * it for `disable` is a harmless no-op (`#handleSetEnabled` reports
+ * "already disabled"). The rest (`test`/`reconnect`/`reauth`/`unauth`) need
+ * a live connection or config entry that a disabled-only name never has —
+ * `#resolveServerForAuth`/`reconnectServer` would report it as not found.
+ */
+const MCP_DISABLED_ONLY_ELIGIBLE_SUBCOMMANDS: ReadonlySet<string> = new Set(["enable", "disable"]);
+
 /**
  * Build getArgumentCompletions for /mcp. Delegates to the generic
  * declarative subcommand completer while the subcommand name itself is
@@ -2489,7 +2501,11 @@ function buildMcpArgumentCompletions(
 
 		let serverNames: string[];
 		try {
-			serverNames = await collectMcpServerNames(runtime.ctx);
+			serverNames = await collectMcpServerNames(
+				runtime.ctx,
+				undefined,
+				MCP_DISABLED_ONLY_ELIGIBLE_SUBCOMMANDS.has(lowerSubcommand),
+			);
 		} catch (error) {
 			logger.warn("MCP server-name autocomplete failed to read config", { error });
 			return null;

packages/coding-agent/test/mcp-name-autocomplete.test.ts

@@ -136,6 +136,30 @@ describe("MCP server-name autocomplete", () => {
 		expect(filtered?.[0]?.value).toBe("enable my-server ");
 	});
 
+	test("/mcp getArgumentCompletions offers a disabled-only discovered name for enable/disable but not test/reconnect/reauth/unauth", async () => {
+		// "discovered-disabled" is a third-party server that was /mcp disable'd:
+		// present only in userConfig.disabledServers, absent from mcpServers, and
+		// no longer reported by the manager (loadAllMCPConfigs drops disabled
+		// sources). #resolveServerForAuth/reconnectServer can't resolve it, so
+		// test/reconnect/reauth/unauth must not suggest it.
+		await Bun.write(
+			getMCPConfigPath("user", projectDir),
+			`${JSON.stringify({ mcpServers: {}, disabledServers: ["discovered-disabled"] }, null, 2)}\n`,
+		);
+		await writeConfig("project", projectDir, {});
+		const { ctx } = createFakeCtx([]);
+		const runtime: TuiSlashCommandRuntime = { ctx };
+		const mcp = buildTuiBuiltinSlashCommands(runtime).find(c => c.name === "mcp");
+		if (!mcp?.getArgumentCompletions) throw new Error("expected /mcp command with getArgumentCompletions");
+
+		expect((await mcp.getArgumentCompletions("enable "))?.map(item => item.label)).toEqual(["discovered-disabled"]);
+		expect((await mcp.getArgumentCompletions("disable "))?.map(item => item.label)).toEqual(["discovered-disabled"]);
+		expect(await mcp.getArgumentCompletions("test ")).toBeNull();
+		expect(await mcp.getArgumentCompletions("reconnect ")).toBeNull();
+		expect(await mcp.getArgumentCompletions("reauth ")).toBeNull();
+		expect(await mcp.getArgumentCompletions("unauth ")).toBeNull();
+	});
+
 	test("/mcp getArgumentCompletions returns null for subcommands that don't take a server name", async () => {
 		await writeConfig("user", projectDir, { "my-server": { type: "stdio", command: "one" } });
 		const { ctx } = createFakeCtx([]);