fix: reload sf source runtime on extension changes

bin/sf-from-source

@@ -53,8 +53,23 @@ if [[ "$IS_HEADLESS" == "1" ]]; then
 	echo "[forge] Launching source CLI..."
 fi
 
-exec "$NODE_BIN" \
-	--import "$SF_SOURCE_ROOT/src/resources/extensions/sf/tests/resolve-ts.mjs" \
-	--experimental-strip-types \
-	--no-warnings \
-	"$SF_SOURCE_ROOT/src/loader.ts" "$@"
+ORIGINAL_ARGS=("$@")
+NEXT_ARGS=("${ORIGINAL_ARGS[@]}")
+while true; do
+	set +e
+	"$NODE_BIN" \
+		--import "$SF_SOURCE_ROOT/src/resources/extensions/sf/tests/resolve-ts.mjs" \
+		--experimental-strip-types \
+		--no-warnings \
+		"$SF_SOURCE_ROOT/src/loader.ts" "${NEXT_ARGS[@]}"
+	status=$?
+	set -e
+
+	if [[ "$status" == "12" && "$IS_HEADLESS" != "1" && -t 0 && -t 1 ]]; then
+		echo "[forge] Runtime reload requested — restarting source CLI with --continue..."
+		NEXT_ARGS=("--continue")
+		continue
+	fi
+
+	exit "$status"
+done

packages/pi-coding-agent/src/core/extensions/runner.test.ts

@@ -144,3 +144,92 @@ describe("ExtensionRunner UI compatibility", () => {
 		}
 	});
 });
+
+describe("ExtensionRunner command conflicts", () => {
+	it("registered_command_when_reserved_for_builtin_delegation_is_hidden_without_warning", () => {
+		const dir = mkdtempSync(join(tmpdir(), "runner-command-test-"));
+		try {
+			const sessionManager = SessionManager.create(dir, dir);
+			const authStorage = AuthStorage.create();
+			const modelRegistry = new ModelRegistry(
+				authStorage,
+				join(dir, "models.json"),
+			);
+			const commands = new Map();
+			commands.set("exit", {
+				name: "exit",
+				description: "Graceful extension exit",
+				handler: async () => undefined,
+			});
+			const extension = {
+				path: "/test/sf-ext",
+				handlers: new Map(),
+				commands,
+				shortcuts: [],
+				diagnostics: [],
+			} as unknown as Extension;
+			const runner = new ExtensionRunner(
+				[extension],
+				makeMinimalRuntime(),
+				dir,
+				sessionManager,
+				modelRegistry,
+			);
+
+			const commandsForAutocomplete = runner.getRegisteredCommands(
+				new Set(["exit"]),
+				new Set(["exit"]),
+			);
+
+			assert.deepEqual(commandsForAutocomplete, []);
+			assert.deepEqual(runner.getCommandDiagnostics(), []);
+			assert.equal(
+				runner.getCommand("exit")?.description,
+				"Graceful extension exit",
+			);
+		} finally {
+			rmSync(dir, { recursive: true, force: true });
+		}
+	});
+
+	it("registered_command_when_reserved_without_delegation_emits_conflict_warning", () => {
+		const dir = mkdtempSync(join(tmpdir(), "runner-command-test-"));
+		try {
+			const sessionManager = SessionManager.create(dir, dir);
+			const authStorage = AuthStorage.create();
+			const modelRegistry = new ModelRegistry(
+				authStorage,
+				join(dir, "models.json"),
+			);
+			const commands = new Map();
+			commands.set("reload", {
+				name: "reload",
+				description: "Duplicate reload",
+				handler: async () => undefined,
+			});
+			const extension = {
+				path: "/test/duplicate-ext",
+				handlers: new Map(),
+				commands,
+				shortcuts: [],
+				diagnostics: [],
+			} as unknown as Extension;
+			const runner = new ExtensionRunner(
+				[extension],
+				makeMinimalRuntime(),
+				dir,
+				sessionManager,
+				modelRegistry,
+			);
+
+			assert.deepEqual(runner.getRegisteredCommands(new Set(["reload"])), []);
+			assert.equal(runner.getCommandDiagnostics().length, 1);
+			assert.match(
+				runner.getCommandDiagnostics()[0]?.message ?? "",
+				/conflicts with built-in commands/,
+			);
+		} finally {
+			rmSync(dir, { recursive: true, force: true });
+		}
+	});
+});

packages/pi-coding-agent/src/core/extensions/runner.ts

@@ -509,7 +509,10 @@ export class ExtensionRunner {
 		return undefined;
 	}
 
-	getRegisteredCommands(reserved?: Set<string>): RegisteredCommand[] {
+	getRegisteredCommands(
+		reserved?: Set<string>,
+		delegatedReserved?: Set<string>,
+	): RegisteredCommand[] {
 		this.commandDiagnostics = [];
 
 		const commands: RegisteredCommand[] = [];
@@ -517,6 +520,9 @@ export class ExtensionRunner {
 		for (const ext of this.extensions) {
 			for (const command of ext.commands.values()) {
 				if (reserved?.has(command.name)) {
+					if (delegatedReserved?.has(command.name)) {
+						continue;
+					}
 					const message = `Extension command '${command.name}' from ${ext.path} conflicts with built-in commands. Skipping.`;
 					this.commandDiagnostics.push({
 						type: "warning",

packages/pi-coding-agent/src/modes/interactive/interactive-mode.ts

@@ -8,6 +8,7 @@ import * as crypto from "node:crypto";
 import * as fs from "node:fs";
 import * as os from "node:os";
 import * as path from "node:path";
+import { fileURLToPath } from "node:url";
 import { listDescendants } from "@singularity-forge/native";
 import type { AgentMessage } from "@singularity-forge/pi-agent-core";
 import type {
@@ -156,6 +157,47 @@ type CompactionQueuedMessage = {
 	mode: "steer" | "followUp";
 };
 
+const INTERACTIVE_RELOAD_EXIT_CODE = 12;
+
+function firstExistingRuntimeFile(candidates: string[]): string | undefined {
+	return candidates.find((candidate) => fs.existsSync(candidate));
+}
+
+/**
+ * Hash runtime modules that cannot be hot-swapped safely inside an active TUI.
+ *
+ * Purpose: distinguish plain resource reloads from package/runtime updates that
+ * need a process restart so the next session uses fresh already-imported code.
+ *
+ * Consumer: handleReloadCommand() before it attempts an in-process reload.
+ */
+function computeInteractiveRuntimeFingerprint(): string {
+	const here = path.dirname(fileURLToPath(import.meta.url));
+	const files = [
+		firstExistingRuntimeFile([
+			path.join(here, "interactive-mode.js"),
+			path.join(here, "interactive-mode.ts"),
+		]),
+		firstExistingRuntimeFile([
+			path.resolve(here, "../../core/extensions/runner.js"),
+			path.resolve(here, "../../core/extensions/runner.ts"),
+		]),
+		firstExistingRuntimeFile([
+			path.resolve(here, "slash-command-handlers.js"),
+			path.resolve(here, "slash-command-handlers.ts"),
+		]),
+	].filter((file): file is string => Boolean(file));
+
+	const hash = crypto.createHash("sha256");
+	for (const file of files.sort()) {
+		hash.update(path.relative(here, file));
+		hash.update("\0");
+		hash.update(fs.readFileSync(file));
+		hash.update("\0");
+	}
+	return hash.digest("hex").slice(0, 16);
+}
+
 /**
  * Options for InteractiveMode initialization.
  */
@@ -202,6 +244,8 @@ export class InteractiveMode {
 	private keybindings: KeybindingsManager;
 	private version: string;
 	private isInitialized = false;
+	private readonly processRestartFingerprint =
+		computeInteractiveRuntimeFingerprint();
 	private onInputCallback?: (text: string) => void;
 	private loadingAnimation: Loader | undefined = undefined;
 	private readonly defaultWorkingMessage = "Working...";
@@ -438,6 +482,7 @@ export class InteractiveMode {
 		const extensionCommands: SlashCommand[] = (
 			this.session.extensionRunner?.getRegisteredCommands(
 				builtinCommandNames,
+				new Set(["exit"]),
 			) ?? []
 		).map((cmd) => ({
 			name: cmd.name,
@@ -3707,6 +3752,15 @@ export class InteractiveMode {
 			return;
 		}
 
+		const currentFingerprint = computeInteractiveRuntimeFingerprint();
+		if (currentFingerprint !== this.processRestartFingerprint) {
+			this.showStatus(
+				"Runtime changed on disk; restarting SF and resuming this session...",
+			);
+			this.ui.requestRender();
+			process.exit(INTERACTIVE_RELOAD_EXIT_CODE);
+		}
+
 		this.resetExtensionUI();
 
 		const loader = new BorderedLoader(