summaryrefslogtreecommitdiff
path: root/packages/cli/src/tools/terminal.tool.ts
blob: dacfb0be9e17d7c30dbf21466fb8460d68073caf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
import {
  spawn,
  SpawnOptions,
  ChildProcessWithoutNullStreams,
} from 'child_process'; // Added 'exec'
import path from 'path';
import os from 'os';
import crypto from 'crypto';
import { promises as fs } from 'fs';
import { BaseTool, ToolResult } from './tools.js';
import { SchemaValidator } from '../utils/schemaValidator.js';
import {
  ToolCallConfirmationDetails,
  ToolConfirmationOutcome,
  ToolExecuteConfirmationDetails,
} from '../ui/types.js'; // Adjust path as needed
import { BackgroundTerminalAnalyzer } from '../utils/BackgroundTerminalAnalyzer.js';
import { getErrorMessage, isNodeError } from '../utils/errors.js';

// --- Interfaces ---
export interface TerminalToolParams {
  command: string;
  description?: string;
  timeout?: number;
  runInBackground?: boolean;
}

// --- Constants ---
const MAX_OUTPUT_LENGTH = 10000; // Default max output length
const DEFAULT_TIMEOUT_MS = 30 * 60 * 1000; // 30 minutes (for foreground commands)
const MAX_TIMEOUT_OVERRIDE_MS = 10 * 60 * 1000; // 10 minutes (max override for foreground)
const BACKGROUND_LAUNCH_TIMEOUT_MS = 15 * 1000; // 15 seconds timeout for *launching* background tasks
const BACKGROUND_POLL_TIMEOUT_MS = 30000; // 30 seconds total polling time for background process status

const BANNED_COMMAND_ROOTS = [
  // Session/flow control (excluding cd)
  'alias',
  'bg',
  'command',
  'declare',
  'dirs',
  'disown',
  'enable',
  'eval',
  'exec',
  'exit',
  'export',
  'fc',
  'fg',
  'getopts',
  'hash',
  'history',
  'jobs',
  'kill',
  'let',
  'local',
  'logout',
  'popd',
  'printf',
  'pushd',
  /* 'pwd' is safe */ 'read',
  'readonly',
  'set',
  'shift',
  'shopt',
  'source',
  'suspend',
  'test',
  'times',
  'trap',
  'type',
  'typeset',
  'ulimit',
  'umask',
  'unalias',
  'unset',
  'wait',
  // Network commands
  'curl',
  'wget',
  'nc',
  'telnet',
  'ssh',
  'scp',
  'ftp',
  'sftp',
  'http',
  'https',
  'ftp',
  'rsync',
  // Browsers/GUI launchers
  'lynx',
  'w3m',
  'links',
  'elinks',
  'httpie',
  'xh',
  'http-prompt',
  'chrome',
  'firefox',
  'safari',
  'edge',
  'xdg-open',
  'open',
];

// --- Helper Type for Command Queue ---
interface QueuedCommand {
  params: TerminalToolParams;
  resolve: (result: ToolResult) => void;
  reject: (error: Error) => void;
  confirmationDetails: ToolExecuteConfirmationDetails | false; // Kept for potential future use
}

/**
 * Implementation of the terminal tool that executes shell commands within a persistent session.
 */
export class TerminalTool extends BaseTool<TerminalToolParams, ToolResult> {
  static Name: string = 'execute_bash_command';

  private readonly rootDirectory: string;
  private readonly outputLimit: number;
  private bashProcess: ChildProcessWithoutNullStreams | null = null;
  private currentCwd: string;
  private isExecuting: boolean = false;
  private commandQueue: QueuedCommand[] = [];
  private currentCommandCleanup: (() => void) | null = null;
  private shouldAlwaysExecuteCommands: Map<string, boolean> = new Map(); // Track confirmation per root command
  private shellReady: Promise<void>;
  private resolveShellReady: (() => void) | undefined; // Definite assignment assertion
  private rejectShellReady: ((reason?: unknown) => void) | undefined; // Definite assignment assertion
  private readonly backgroundTerminalAnalyzer: BackgroundTerminalAnalyzer;

  constructor(rootDirectory: string, outputLimit: number = MAX_OUTPUT_LENGTH) {
    const toolDisplayName = 'Terminal';
    // --- LLM-Facing Description ---
    // Updated description for background tasks to mention polling and LLM analysis
    const toolDescription = `Executes one or more bash commands sequentially in a secure and persistent interactive shell session. Can run commands in the foreground (waiting for completion) or background (returning after launch, with subsequent status polling).

Core Functionality:
* Starts in project root: '${path.basename(rootDirectory)}'. Current Directory starts as: ${rootDirectory} (will update based on 'cd' commands).
* Persistent State: Environment variables and the current working directory (\`pwd\`) persist between calls to this tool.
* **Execution Modes:**
    * **Foreground (default):** Waits for the command to complete. Captures stdout, stderr, and exit code. Output is truncated if it exceeds ${outputLimit} characters.
    * **Background (\`runInBackground: true\`):** Appends \`&\` to the command and redirects its output to temporary files. Returns *after* the command is launched, providing the Process ID (PID) and launch status. Subsequently, the tool **polls** for the background process status for up to ${BACKGROUND_POLL_TIMEOUT_MS / 1000} seconds. Once the process finishes or polling times out, the tool reads the captured stdout/stderr from the temporary files, runs an internal LLM analysis on the output, cleans up the files, and returns the final status, captured output, and analysis.
* Timeout: Optional timeout per 'execute' call (default: ${DEFAULT_TIMEOUT_MS / 60000} min, max override: ${MAX_TIMEOUT_OVERRIDE_MS / 60000} min for foreground). Background *launch* has a fixed shorter timeout (${BACKGROUND_LAUNCH_TIMEOUT_MS / 1000}s) for the launch attempt itself. Background *polling* has its own timeout (${BACKGROUND_POLL_TIMEOUT_MS / 1000}s). Timeout attempts SIGINT for foreground commands.

Usage Guidance & Restrictions:

1.  **Directory/File Verification (IMPORTANT):**
    * BEFORE executing commands that create files or directories (e.g., \`mkdir foo/bar\`, \`touch new/file.txt\`, \`git clone ...\`), use the dedicated File System tool (e.g., 'list_directory') to verify the target parent directory exists and is the correct location.
    * Example: Before running \`mkdir foo/bar\`, first use the File System tool to check that \`foo\` exists in the current directory (\`${rootDirectory}\` initially, check current CWD if it changed).

2.  **Use Specialized Tools (CRITICAL):**
    * Do NOT use this tool for filesystem searching (\`find\`, \`grep\`). Use the dedicated Search tool instead.
    * Do NOT use this tool for reading files (\`cat\`, \`head\`, \`tail\`, \`less\`, \`more\`). Use the dedicated File Reader tool instead.
    * Do NOT use this tool for listing files (\`ls\`). Use the dedicated File System tool ('list_directory') instead. Relying on this tool's output for directory structure is unreliable due to potential truncation and lack of structured data.

3.  **Security & Banned Commands:**
    * Certain commands are banned for security (e.g., network: ${BANNED_COMMAND_ROOTS.filter((c) => ['curl', 'wget', 'ssh'].includes(c)).join(', ')}; session: ${BANNED_COMMAND_ROOTS.filter((c) => ['exit', 'export', 'kill'].includes(c)).join(', ')}; etc.). The full list is extensive.
    * If you attempt a banned command, this tool will return an error explaining the restriction. You MUST relay this error clearly to the user.

4.  **Command Execution Notes:**
    * Chain multiple commands using shell operators like ';' or '&&'. Do NOT use newlines within the 'command' parameter string itself (newlines are fine inside quoted arguments).
    * The shell's current working directory is tracked internally. While \`cd\` is permitted if the user explicitly asks or it's necessary for a workflow, **strongly prefer** using absolute paths or paths relative to the *known* current working directory to avoid errors. Check the '(Executed in: ...)' part of the previous command's output for the CWD.
        * Good example (if CWD is /workspace/project): \`pytest tests/unit\` or \`ls /workspace/project/data\`
        * Less preferred: \`cd tests && pytest unit\` (only use if necessary or requested)

5.  **Background Tasks (\`runInBackground: true\`):**
    * Use this for commands that are intended to run continuously (e.g., \`node server.js\`, \`npm start\`).
    * The tool initially returns success if the process *launches* successfully, along with its PID.
    * **Polling & Final Result:** The tool then monitors the process. The *final* result (delivered after polling completes or times out) will include:
        * The final status (completed or timed out).
        * The complete stdout and stderr captured in temporary files (truncated if necessary).
        * An LLM-generated analysis/summary of the output.
    * The initial exit code (usually 0) signifies successful *launching*; the final status indicates completion or timeout after polling.

Use this tool for running build steps (\`npm install\`, \`make\`), linters (\`eslint .\`), test runners (\`pytest\`, \`jest\`), code formatters (\`prettier --write .\`), package managers (\`pip install\`), version control operations (\`git status\`, \`git diff\`), starting background servers/services (\`node server.js --runInBackground true\`), or other safe, standard command-line operations within the project workspace.`;
    // --- Parameter Schema ---
    const toolParameterSchema = {
      type: 'object',
      properties: {
        command: {
          description: `The exact bash command or sequence of commands (using ';' or '&&') to execute. Must adhere to usage guidelines. Example: 'npm install && npm run build'`,
          type: 'string',
        },
        description: {
          description: `Optional: A brief, user-centric explanation of what the command does and why it's being run. Used for logging and confirmation prompts. Example: 'Install project dependencies'`,
          type: 'string',
        },
        timeout: {
          description: `Optional execution time limit in milliseconds for FOREGROUND commands. Max ${MAX_TIMEOUT_OVERRIDE_MS}ms (${MAX_TIMEOUT_OVERRIDE_MS / 60000} min). Defaults to ${DEFAULT_TIMEOUT_MS}ms (${DEFAULT_TIMEOUT_MS / 60000} min) if not specified or invalid. Ignored if 'runInBackground' is true.`,
          type: 'number',
        },
        runInBackground: {
          description: `If true, execute the command in the background using '&'. Defaults to false. Use for servers or long tasks.`,
          type: 'boolean',
        },
      },
      required: ['command'],
    };

    super(
      TerminalTool.Name,
      toolDisplayName,
      toolDescription,
      toolParameterSchema,
    );

    this.rootDirectory = path.resolve(rootDirectory);
    this.currentCwd = this.rootDirectory;
    this.outputLimit = outputLimit;
    this.shellReady = new Promise((resolve, reject) => {
      this.resolveShellReady = resolve;
      this.rejectShellReady = reject;
    });
    this.backgroundTerminalAnalyzer = new BackgroundTerminalAnalyzer();

    this.initializeShell();
  }

  // --- Shell Initialization and Management (largely unchanged) ---
  private initializeShell() {
    if (this.bashProcess) {
      try {
        this.bashProcess.kill();
      } catch {
        /* Ignore */
      }
    }

    const spawnOptions: SpawnOptions = {
      cwd: this.rootDirectory,
      shell: true,
      env: { ...process.env },
      stdio: ['pipe', 'pipe', 'pipe'],
    };

    try {
      const bashPath = os.platform() === 'win32' ? 'bash.exe' : 'bash';
      this.bashProcess = spawn(
        bashPath,
        ['-s'],
        spawnOptions,
      ) as ChildProcessWithoutNullStreams;
      this.currentCwd = this.rootDirectory; // Reset CWD on restart

      this.bashProcess.on('error', (err) => {
        console.error('Persistent Bash Error:', err);
        this.rejectShellReady?.(err); // Use optional chaining as reject might be cleared
        this.bashProcess = null;
        this.isExecuting = false;
        this.clearQueue(
          new Error(`Persistent bash process failed to start: ${err.message}`),
        );
      });

      this.bashProcess.on('close', (code, signal) => {
        this.bashProcess = null;
        this.isExecuting = false;
        // Only reject if it hasn't been resolved/rejected already
        this.rejectShellReady?.(
          new Error(
            `Persistent bash process exited (code: ${code}, signal: ${signal})`,
          ),
        );
        // Reset shell readiness promise for reinitialization attempts
        this.shellReady = new Promise((resolve, reject) => {
          this.resolveShellReady = resolve;
          this.rejectShellReady = reject;
        });
        this.clearQueue(
          new Error(
            `Persistent bash process exited unexpectedly (code: ${code}, signal: ${signal}). State is lost. Queued commands cancelled.`,
          ),
        );
        // Attempt to reinitialize after a short delay
        setTimeout(() => this.initializeShell(), 1000);
      });

      // Readiness check - ensure shell is responsive
      // Slightly longer timeout to allow shell init
      setTimeout(() => {
        if (this.bashProcess && !this.bashProcess.killed) {
          this.resolveShellReady?.(); // Use optional chaining
        } else if (!this.bashProcess) {
          // Error likely already handled by 'error' or 'close' event
        } else {
          // Process was killed during init?
          this.rejectShellReady?.(
            new Error('Shell killed during initialization'),
          );
        }
      }, 1000); // Increase readiness check timeout slightly
    } catch (error: unknown) {
      console.error('Failed to spawn persistent bash:', error);
      this.rejectShellReady?.(error); // Use optional chaining
      this.bashProcess = null;
      this.clearQueue(
        new Error(`Failed to spawn persistent bash: ${getErrorMessage(error)}`),
      );
    }
  }

  // --- Parameter Validation (unchanged) ---
  validateToolParams(params: TerminalToolParams): string | null {
    if (
      !SchemaValidator.validate(
        this.parameterSchema as Record<string, unknown>,
        params,
      )
    ) {
      return `Parameters failed schema validation.`;
    }

    const commandOriginal = params.command.trim();
    if (!commandOriginal) {
      return 'Command cannot be empty.';
    }
    const commandParts = commandOriginal.split(/[\s;&&|]+/);

    for (const part of commandParts) {
      if (!part) continue;
      // Improved check: strip leading special chars before checking basename
      const cleanPart =
        part
          .replace(/^[^a-zA-Z0-9]+/, '')
          .split(/[/\\]/)
          .pop() || part.replace(/^[^a-zA-Z0-9]+/, '');
      if (cleanPart && BANNED_COMMAND_ROOTS.includes(cleanPart.toLowerCase())) {
        return `Command contains a banned keyword: '${cleanPart}'. Banned list includes network tools, session control, etc.`;
      }
    }

    if (
      params.timeout !== undefined &&
      (typeof params.timeout !== 'number' || params.timeout <= 0)
    ) {
      return 'Timeout must be a positive number of milliseconds.';
    }

    return null; // Parameters are valid
  }

  // --- Description and Confirmation (unchanged) ---
  getDescription(params: TerminalToolParams): string {
    return params.description || params.command;
  }

  async shouldConfirmExecute(
    params: TerminalToolParams,
  ): Promise<ToolCallConfirmationDetails | false> {
    const rootCommand =
      params.command
        .trim()
        .split(/[\s;&&|]+/)[0]
        ?.split(/[/\\]/)
        .pop() || 'unknown';

    if (this.shouldAlwaysExecuteCommands.get(rootCommand)) {
      return false;
    }

    const description = this.getDescription(params);

    const confirmationDetails: ToolExecuteConfirmationDetails = {
      title: 'Confirm Shell Command',
      command: params.command,
      rootCommand,
      description: `Execute in '${this.currentCwd}':\n${description}`,
      onConfirm: async (outcome: ToolConfirmationOutcome) => {
        if (outcome === ToolConfirmationOutcome.ProceedAlways) {
          this.shouldAlwaysExecuteCommands.set(rootCommand, true);
        }
      },
    };
    return confirmationDetails;
  }

  // --- Command Execution and Queueing (unchanged structure) ---
  async execute(params: TerminalToolParams): Promise<ToolResult> {
    const validationError = this.validateToolParams(params);
    if (validationError) {
      return {
        llmContent: `Command rejected: ${params.command}\nReason: ${validationError}`,
        returnDisplay: `Error: ${validationError}`,
      };
    }

    // Assume confirmation is handled before calling execute

    return new Promise((resolve) => {
      const queuedItem: QueuedCommand = {
        params,
        resolve, // Resolve outer promise
        reject: (error) =>
          resolve({
            // Handle internal errors by resolving outer promise
            llmContent: `Internal tool error for command: ${params.command}\nError: ${error.message}`,
            returnDisplay: `Internal Tool Error: ${error.message}`,
          }),
        confirmationDetails: false, // Placeholder
      };
      this.commandQueue.push(queuedItem);
      // Ensure queue processing is triggered *after* adding the item
      setImmediate(() => this.triggerQueueProcessing());
    });
  }

  private async triggerQueueProcessing(): Promise<void> {
    if (this.isExecuting || this.commandQueue.length === 0) {
      return;
    }

    this.isExecuting = true;
    const { params, resolve, reject } = this.commandQueue.shift()!;

    try {
      await this.shellReady; // Wait for the shell to be ready (or reinitialized)
      if (!this.bashProcess || this.bashProcess.killed) {
        // Check if killed
        throw new Error(
          'Persistent bash process is not available or was killed.',
        );
      }
      // **** Core execution logic call ****
      const result = await this.executeCommandInShell(params);
      resolve(result); // Resolve the specific command's promise
    } catch (error: unknown) {
      console.error(`Error executing command "${params.command}":`, error);

      if (error instanceof Error) {
        reject(error);
      } else {
        reject(new Error('Unknown error occurred: ' + JSON.stringify(error)));
      }
    } finally {
      this.isExecuting = false;
      // Use setImmediate to avoid potential deep recursion
      setImmediate(() => this.triggerQueueProcessing());
    }
  }

  // --- **** MODIFIED: Core Command Execution Logic **** ---
  private executeCommandInShell(
    params: TerminalToolParams,
  ): Promise<ToolResult> {
    // Define temp file paths here to be accessible throughout
    let tempStdoutPath: string | null = null;
    let tempStderrPath: string | null = null;
    let originalResolve: (value: ToolResult | PromiseLike<ToolResult>) => void; // To pass to polling
    let originalReject: (reason?: unknown) => void;

    const promise = new Promise<ToolResult>((resolve, reject) => {
      originalResolve = resolve; // Assign outer scope resolve
      originalReject = reject; // Assign outer scope reject

      if (!this.bashProcess) {
        return reject(
          new Error('Bash process is not running. Cannot execute command.'),
        );
      }

      const isBackgroundTask = params.runInBackground ?? false;
      const commandUUID = crypto.randomUUID();
      const startDelimiter = `::START_CMD_${commandUUID}::`;
      const endDelimiter = `::END_CMD_${commandUUID}::`;
      const exitCodeDelimiter = `::EXIT_CODE_${commandUUID}::`;
      const pidDelimiter = `::PID_${commandUUID}::`; // For background PID

      // --- Initialize Temp Files for Background Task ---
      if (isBackgroundTask) {
        try {
          const tempDir = os.tmpdir();
          tempStdoutPath = path.join(tempDir, `term_out_${commandUUID}.log`);
          tempStderrPath = path.join(tempDir, `term_err_${commandUUID}.log`);
        } catch (err: unknown) {
          // If temp dir setup fails, reject immediately
          return reject(
            new Error(
              `Failed to determine temporary directory: ${getErrorMessage(err)}`,
            ),
          );
        }
      }
      // --- End Temp File Init ---

      let stdoutBuffer = ''; // For launch output
      let stderrBuffer = ''; // For launch output
      let commandOutputStarted = false;
      let exitCode: number | null = null;
      let backgroundPid: number | null = null; // Store PID
      let receivedEndDelimiter = false;

      // Timeout only applies to foreground execution or background *launch* phase
      const effectiveTimeout = isBackgroundTask
        ? BACKGROUND_LAUNCH_TIMEOUT_MS
        : Math.min(
            params.timeout ?? DEFAULT_TIMEOUT_MS, // Use default timeout if not provided
            MAX_TIMEOUT_OVERRIDE_MS,
          );

      let onStdoutData: ((data: Buffer) => void) | null = null;
      let onStderrData: ((data: Buffer) => void) | null = null;
      let launchTimeoutId: NodeJS.Timeout | null = null; // Renamed for clarity

      launchTimeoutId = setTimeout(() => {
        const timeoutMessage = isBackgroundTask
          ? `Background command launch timed out after ${effectiveTimeout}ms.`
          : `Command timed out after ${effectiveTimeout}ms.`;

        if (!isBackgroundTask && this.bashProcess && !this.bashProcess.killed) {
          try {
            this.bashProcess.stdin.write('\x03'); // Ctrl+C for foreground timeout
          } catch (e: unknown) {
            console.error('Error writing SIGINT on timeout:', e);
          }
        }
        // Store listeners before calling cleanup, as cleanup nullifies them
        const listenersToClean = { onStdoutData, onStderrData };
        cleanupListeners(listenersToClean); // Clean up listeners for this command

        // Clean up temp files if background launch timed out
        if (isBackgroundTask && tempStdoutPath && tempStderrPath) {
          this.cleanupTempFiles(tempStdoutPath, tempStderrPath).catch((err) => {
            console.warn(
              `Error cleaning up temp files on timeout: ${err.message}`,
            );
          });
        }

        // Resolve the main promise with timeout info
        originalResolve({
          llmContent: `Command execution failed: ${timeoutMessage}\nCommand: ${params.command}\nExecuted in: ${this.currentCwd}\n${isBackgroundTask ? 'Mode: Background Launch' : `Mode: Foreground\nTimeout Limit: ${effectiveTimeout}ms`}\nPartial Stdout (Launch):\n${this.truncateOutput(stdoutBuffer)}\nPartial Stderr (Launch):\n${this.truncateOutput(stderrBuffer)}\nNote: ${isBackgroundTask ? 'Launch failed or took too long.' : 'Attempted interrupt (SIGINT). Shell state might be unpredictable if command ignored interrupt.'}`,
          returnDisplay: `Timeout: ${timeoutMessage}`,
        });
      }, effectiveTimeout);

      // --- Data processing logic (refined slightly) ---
      const processDataChunk = (chunk: string, isStderr: boolean): boolean => {
        let dataToProcess = chunk;

        if (!commandOutputStarted) {
          const startIndex = dataToProcess.indexOf(startDelimiter);
          if (startIndex !== -1) {
            commandOutputStarted = true;
            dataToProcess = dataToProcess.substring(
              startIndex + startDelimiter.length,
            );
          } else {
            return false; // Still waiting for start delimiter
          }
        }

        // Process PID delimiter (mostly expected on stderr for background)
        const pidIndex = dataToProcess.indexOf(pidDelimiter);
        if (pidIndex !== -1) {
          // Extract PID value strictly between delimiter and newline/end
          const pidMatch = dataToProcess
            .substring(pidIndex + pidDelimiter.length)
            .match(/^(\d+)/);
          if (pidMatch?.[1]) {
            backgroundPid = parseInt(pidMatch[1], 10);
            const pidEndIndex =
              pidIndex + pidDelimiter.length + pidMatch[1].length;
            const beforePid = dataToProcess.substring(0, pidIndex);
            if (isStderr) stderrBuffer += beforePid;
            else stdoutBuffer += beforePid;
            dataToProcess = dataToProcess.substring(pidEndIndex);
          } else {
            // Consume delimiter even if no number followed
            const beforePid = dataToProcess.substring(0, pidIndex);
            if (isStderr) stderrBuffer += beforePid;
            else stdoutBuffer += beforePid;
            dataToProcess = dataToProcess.substring(
              pidIndex + pidDelimiter.length,
            );
          }
        }

        // Process Exit Code delimiter
        const exitCodeIndex = dataToProcess.indexOf(exitCodeDelimiter);
        if (exitCodeIndex !== -1) {
          const exitCodeMatch = dataToProcess
            .substring(exitCodeIndex + exitCodeDelimiter.length)
            .match(/^(\d+)/);
          if (exitCodeMatch?.[1]) {
            exitCode = parseInt(exitCodeMatch[1], 10);
            const beforeExitCode = dataToProcess.substring(0, exitCodeIndex);
            if (isStderr) stderrBuffer += beforeExitCode;
            else stdoutBuffer += beforeExitCode;
            dataToProcess = dataToProcess.substring(
              exitCodeIndex +
                exitCodeDelimiter.length +
                exitCodeMatch[1].length,
            );
          } else {
            const beforeExitCode = dataToProcess.substring(0, exitCodeIndex);
            if (isStderr) stderrBuffer += beforeExitCode;
            else stdoutBuffer += beforeExitCode;
            dataToProcess = dataToProcess.substring(
              exitCodeIndex + exitCodeDelimiter.length,
            );
          }
        }

        // Process End delimiter
        const endDelimiterIndex = dataToProcess.indexOf(endDelimiter);
        if (endDelimiterIndex !== -1) {
          receivedEndDelimiter = true;
          const beforeEndDelimiter = dataToProcess.substring(
            0,
            endDelimiterIndex,
          );
          if (isStderr) stderrBuffer += beforeEndDelimiter;
          else stdoutBuffer += beforeEndDelimiter;
          // Consume delimiter and potentially the exit code echoed after it
          const afterEndDelimiter = dataToProcess.substring(
            endDelimiterIndex + endDelimiter.length,
          );
          const exitCodeEchoMatch = afterEndDelimiter.match(/^(\d+)/);
          dataToProcess = exitCodeEchoMatch
            ? afterEndDelimiter.substring(exitCodeEchoMatch[1].length)
            : afterEndDelimiter;
        }

        // Append remaining data
        if (dataToProcess.length > 0) {
          if (isStderr) stderrBuffer += dataToProcess;
          else stdoutBuffer += dataToProcess;
        }

        // Check completion criteria
        if (receivedEndDelimiter && exitCode !== null) {
          setImmediate(cleanupAndResolve); // Use setImmediate
          return true; // Signal completion of this command's stream processing
        }

        return false; // More data or delimiters expected
      };

      // Assign listeners
      onStdoutData = (data: Buffer) => processDataChunk(data.toString(), false);
      onStderrData = (data: Buffer) => processDataChunk(data.toString(), true);

      // --- Cleanup Logic ---
      // Pass listeners to allow cleanup even if they are nullified later
      const cleanupListeners = (listeners?: {
        onStdoutData: ((data: Buffer) => void) | null;
        onStderrData: ((data: Buffer) => void) | null;
      }) => {
        if (launchTimeoutId) clearTimeout(launchTimeoutId);
        launchTimeoutId = null;

        // Use passed-in listeners if available, otherwise use current scope's
        const stdoutListener = listeners?.onStdoutData ?? onStdoutData;
        const stderrListener = listeners?.onStderrData ?? onStderrData;

        if (this.bashProcess && !this.bashProcess.killed) {
          if (stdoutListener)
            this.bashProcess.stdout.removeListener('data', stdoutListener);
          if (stderrListener)
            this.bashProcess.stderr.removeListener('data', stderrListener);
        }
        // Only nullify the *current command's* cleanup reference if it matches
        if (this.currentCommandCleanup === cleanupListeners) {
          this.currentCommandCleanup = null;
        }
        // Nullify the listener references in the outer scope regardless
        onStdoutData = null;
        onStderrData = null;
      };
      // Store *this specific* cleanup function instance for the current command
      this.currentCommandCleanup = cleanupListeners;

      // --- Final Resolution / Polling Logic ---
      const cleanupAndResolve = async () => {
        // Prevent double execution if cleanup was already called (e.g., by timeout)
        if (
          !this.currentCommandCleanup ||
          this.currentCommandCleanup !== cleanupListeners
        ) {
          // Ensure temp files are cleaned if this command was superseded but might have created them
          if (isBackgroundTask && tempStdoutPath && tempStderrPath) {
            this.cleanupTempFiles(tempStdoutPath, tempStderrPath).catch(
              (err) => {
                console.warn(
                  `Error cleaning up temp files for superseded command: ${err.message}`,
                );
              },
            );
          }
          return;
        }

        // Capture initial output *before* cleanup nullifies buffers indirectly
        const launchStdout = this.truncateOutput(stdoutBuffer);
        const launchStderr = this.truncateOutput(stderrBuffer);

        // Store listeners before calling cleanup
        const listenersToClean = { onStdoutData, onStderrData };
        cleanupListeners(listenersToClean); // Remove listeners and clear launch timeout NOW

        // --- Error check for missing exit code ---
        if (exitCode === null) {
          console.error(
            `CRITICAL: Command "${params.command}" (background: ${isBackgroundTask}) finished delimiter processing but exitCode is null.`,
          );
          const errorMode = isBackgroundTask
            ? 'Background Launch'
            : 'Foreground';
          if (isBackgroundTask && tempStdoutPath && tempStderrPath) {
            await this.cleanupTempFiles(tempStdoutPath, tempStderrPath);
          }
          originalResolve({
            // Use originalResolve as this is a failure *before* polling starts
            llmContent: `Command: ${params.command}\nExecuted in: ${this.currentCwd}\nMode: ${errorMode}\nExit Code: -2 (Internal Error: Exit code not captured)\nStdout (during setup):\n${launchStdout}\nStderr (during setup):\n${launchStderr}`,
            returnDisplay:
              `Internal Error: Failed to capture command exit code.\n${launchStdout}\nStderr: ${launchStderr}`.trim(),
          });
          return;
        }

        // --- CWD Update Logic (Only for Foreground Success or 'cd') ---
        let cwdUpdateError = '';
        if (!isBackgroundTask) {
          // Only run for foreground
          const mightChangeCwd = params.command.trim().startsWith('cd ');
          if (exitCode === 0 || mightChangeCwd) {
            try {
              const latestCwd = await this.getCurrentShellCwd();
              if (this.currentCwd !== latestCwd) {
                this.currentCwd = latestCwd;
              }
            } catch (e: unknown) {
              if (exitCode === 0) {
                // Only warn if the command itself succeeded
                cwdUpdateError = `\nWarning: Failed to verify/update current working directory after command: ${getErrorMessage(e)}`;
                console.error(
                  'Failed to update CWD after successful command:',
                  e,
                );
              }
            }
          }
        }
        // --- End CWD Update ---

        // --- Result Formatting & Polling Decision ---
        if (isBackgroundTask) {
          const launchSuccess = exitCode === 0;
          const pidString =
            backgroundPid !== null ? backgroundPid.toString() : 'Not Captured';

          // Check if polling should start
          if (
            launchSuccess &&
            backgroundPid !== null &&
            tempStdoutPath &&
            tempStderrPath
          ) {
            // --- START POLLING ---
            // Don't await this, let it run in the background and resolve the original promise later
            this.inspectBackgroundProcess(
              backgroundPid,
              params.command,
              this.currentCwd, // CWD at time of launch
              launchStdout, // Initial output captured during launch
              launchStderr, // Initial output captured during launch
              tempStdoutPath, // Path for final stdout
              tempStderrPath, // Path for final stderr
              originalResolve, // The resolve function of the main promise
            );
            // IMPORTANT: Do NOT resolve the promise here. pollBackgroundProcess will do it.
            // --- END POLLING ---
          } else {
            // Background launch failed OR PID was not captured OR temp files missing
            const reason =
              backgroundPid === null
                ? 'PID not captured'
                : `Launch failed (Exit Code: ${exitCode})`;
            const displayMessage = `Failed to launch process in background (${reason})`;
            console.error(
              `Background launch failed for command: ${params.command}. Reason: ${reason}`,
            ); // ERROR LOG
            // Ensure cleanup of temp files if launch failed
            if (tempStdoutPath && tempStderrPath) {
              await this.cleanupTempFiles(tempStdoutPath, tempStderrPath);
            }
            originalResolve({
              // Use originalResolve as polling won't start
              llmContent: `Background Command Launch Failed: ${params.command}\nExecuted in: ${this.currentCwd}\nReason: ${reason}\nPID: ${pidString}\nExit Code (Launch): ${exitCode}\nStdout (During Launch):\n${launchStdout}\nStderr (During Launch):\n${launchStderr}`,
              returnDisplay: displayMessage,
            });
          }
        } else {
          // --- Foreground task result (resolve immediately) ---
          let displayOutput = '';
          const stdoutTrimmed = launchStdout.trim();
          const stderrTrimmed = launchStderr.trim();

          if (stderrTrimmed) {
            displayOutput = stderrTrimmed;
          } else if (stdoutTrimmed) {
            displayOutput = stdoutTrimmed;
          }

          if (exitCode !== 0 && !displayOutput) {
            displayOutput = `Failed with exit code: ${exitCode}`;
          } else if (exitCode === 0 && !displayOutput) {
            displayOutput = `Success (no output)`;
          }

          originalResolve({
            // Use originalResolve for foreground result
            llmContent: `Command: ${params.command}\nExecuted in: ${this.currentCwd}\nExit Code: ${exitCode}\nStdout:\n${launchStdout}\nStderr:\n${launchStderr}${cwdUpdateError}`,
            returnDisplay: displayOutput.trim() || `Exit Code: ${exitCode}`, // Ensure some display
          });
          // --- End Foreground Result ---
        }
      }; // End of cleanupAndResolve

      // --- Attach listeners ---
      if (!this.bashProcess || this.bashProcess.killed) {
        console.error(
          'Bash process lost or killed before listeners could be attached.',
        );
        // Ensure temp files are cleaned up if they exist
        if (isBackgroundTask && tempStdoutPath && tempStderrPath) {
          this.cleanupTempFiles(tempStdoutPath, tempStderrPath).catch((err) => {
            console.warn(
              `Error cleaning up temp files on attach failure: ${err.message}`,
            );
          });
        }
        return originalReject(
          new Error(
            'Bash process lost or killed before listeners could be attached.',
          ),
        );
      }
      // Defensive remove shouldn't be strictly necessary with current cleanup logic, but harmless
      // if (onStdoutData) this.bashProcess.stdout.removeListener('data', onStdoutData);
      // if (onStderrData) this.bashProcess.stderr.removeListener('data', onStderrData);

      // Attach the fresh listeners
      if (onStdoutData) this.bashProcess.stdout.on('data', onStdoutData);
      if (onStderrData) this.bashProcess.stderr.on('data', onStderrData);

      // --- Construct and Write Command ---
      let commandToWrite: string;
      if (isBackgroundTask && tempStdoutPath && tempStderrPath) {
        // Background: Redirect command's stdout/stderr to temp files.
        // Use subshell { ... } > file 2> file to redirect the command inside.
        // Capture PID of the subshell. Capture exit code of the subshell launch.
        // Ensure the subshell itself doesn't interfere with delimiter capture on stderr.
        commandToWrite = `echo "${startDelimiter}"; { { ${params.command} > "${tempStdoutPath}" 2> "${tempStderrPath}"; } & } 2>/dev/null; __LAST_PID=$!; echo "${pidDelimiter}$__LAST_PID" >&2; echo "${exitCodeDelimiter}$?" >&2; echo "${endDelimiter}$?" >&1\n`;
      } else if (!isBackgroundTask) {
        // Foreground: Original structure. Capture command exit code.
        commandToWrite = `echo "${startDelimiter}"; ${params.command}; __EXIT_CODE=$?; echo "${exitCodeDelimiter}$__EXIT_CODE" >&2; echo "${endDelimiter}$__EXIT_CODE" >&1\n`;
      } else {
        // Should not happen if background task setup failed, but handle defensively
        return originalReject(
          new Error(
            'Internal setup error: Missing temporary file paths for background execution.',
          ),
        );
      }

      try {
        if (this.bashProcess?.stdin?.writable) {
          this.bashProcess.stdin.write(commandToWrite, (err) => {
            if (err) {
              console.error(
                `Error writing command "${params.command}" to bash stdin (callback):`,
                err,
              );
              // Store listeners before calling cleanup
              const listenersToClean = {
                onStdoutData,
                onStderrData,
              };
              cleanupListeners(listenersToClean); // Attempt cleanup
              if (isBackgroundTask && tempStdoutPath && tempStderrPath) {
                this.cleanupTempFiles(tempStdoutPath, tempStderrPath).catch(
                  (e) => console.warn(`Cleanup failed: ${e.message}`),
                );
              }
              originalReject(
                new Error(
                  `Shell stdin write error: ${err.message}. Command likely did not execute.`,
                ),
              );
            }
          });
        } else {
          throw new Error(
            'Shell stdin is not writable or process closed when attempting to write command.',
          );
        }
      } catch (e: unknown) {
        console.error(
          `Error writing command "${params.command}" to bash stdin (sync):`,
          e,
        );
        // Store listeners before calling cleanup
        const listenersToClean = { onStdoutData, onStderrData };
        cleanupListeners(listenersToClean); // Attempt cleanup
        if (isBackgroundTask && tempStdoutPath && tempStderrPath) {
          this.cleanupTempFiles(tempStdoutPath, tempStderrPath).catch((err) =>
            console.warn(`Cleanup failed: ${err.message}`),
          );
        }
        originalReject(
          new Error(
            `Shell stdin write exception: ${getErrorMessage(e)}. Command likely did not execute.`,
          ),
        );
      }
    }); // End of main promise constructor

    return promise; // Return the promise created at the top
  } // End of executeCommandInShell

  // --- **** NEW: Background Process Polling **** ---
  private async inspectBackgroundProcess(
    pid: number,
    command: string,
    cwd: string,
    initialStdout: string, // Stdout during launch phase
    initialStderr: string, // Stderr during launch phase
    tempStdoutPath: string, // Path to redirected stdout
    tempStderrPath: string, // Path to redirected stderr
    resolve: (value: ToolResult | PromiseLike<ToolResult>) => void, // The original promise's resolve
  ): Promise<void> {
    // This function manages its own lifecycle but resolves the outer promise
    let finalStdout = '';
    let finalStderr = '';
    let llmAnalysis = '';
    let fileReadError = '';

    // --- Call LLM Analysis ---
    try {
      const { status, summary } = await this.backgroundTerminalAnalyzer.analyze(
        pid,
        tempStdoutPath,
        tempStderrPath,
        command,
      );
      if (status === 'Unknown') llmAnalysis = `LLM analysis failed: ${summary}`;
      else llmAnalysis = summary;
    } catch (llmerror: unknown) {
      console.error(
        `LLM analysis failed for PID ${pid} command "${command}":`,
        llmerror,
      );
      llmAnalysis = `LLM analysis failed: ${getErrorMessage(llmerror)}`; // Include error in analysis placeholder
    }
    // --- End LLM Call ---

    try {
      finalStdout = await fs.readFile(tempStdoutPath, 'utf-8');
      finalStderr = await fs.readFile(tempStderrPath, 'utf-8');
    } catch (err: unknown) {
      console.error(`Error reading temp output files for PID ${pid}:`, err);
      fileReadError = `\nWarning: Failed to read temporary output files (${getErrorMessage(err)}). Final output may be incomplete.`;
    }

    // --- Clean up temp files ---
    await this.cleanupTempFiles(tempStdoutPath, tempStderrPath);
    // --- End Cleanup ---

    const truncatedFinalStdout = this.truncateOutput(finalStdout);
    const truncatedFinalStderr = this.truncateOutput(finalStderr);

    // Resolve the original promise passed into pollBackgroundProcess
    resolve({
      llmContent: `Background Command: ${command}\nLaunched in: ${cwd}\nPID: ${pid}\n--- LLM Analysis ---\n${llmAnalysis}\n--- Final Stdout (from ${path.basename(tempStdoutPath)}) ---\n${truncatedFinalStdout}\n--- Final Stderr (from ${path.basename(tempStderrPath)}) ---\n${truncatedFinalStderr}\n--- Launch Stdout ---\n${initialStdout}\n--- Launch Stderr ---\n${initialStderr}${fileReadError}`,
      returnDisplay: `(PID: ${pid}): ${this.truncateOutput(llmAnalysis, 200)}`,
    });
  } // End of pollBackgroundProcess

  // --- **** NEW: Helper to cleanup temp files **** ---
  private async cleanupTempFiles(
    stdoutPath: string | null,
    stderrPath: string | null,
  ): Promise<void> {
    const unlinkQuietly = async (filePath: string | null) => {
      if (!filePath) return;
      try {
        await fs.unlink(filePath);
      } catch (err: unknown) {
        // Ignore errors like file not found (it might have been deleted already or failed to create)
        if (!isNodeError(err) || err.code !== 'ENOENT') {
          console.warn(
            `Failed to delete temporary file '${filePath}': ${getErrorMessage(err)}`,
          );
        }
      }
    };
    // Run deletions concurrently and wait for both
    await Promise.all([unlinkQuietly(stdoutPath), unlinkQuietly(stderrPath)]);
  }

  // --- Get CWD (mostly unchanged, added robustness) ---
  private getCurrentShellCwd(): Promise<string> {
    return new Promise((resolve, reject) => {
      if (
        !this.bashProcess ||
        !this.bashProcess.stdin?.writable ||
        this.bashProcess.killed
      ) {
        return reject(
          new Error(
            'Shell not running, stdin not writable, or killed for PWD check',
          ),
        );
      }

      const pwdUuid = crypto.randomUUID();
      const pwdDelimiter = `::PWD_${pwdUuid}::`;
      let pwdOutput = '';
      let onPwdData: ((data: Buffer) => void) | null = null;
      let onPwdError: ((data: Buffer) => void) | null = null; // To catch errors during pwd
      let pwdTimeoutId: NodeJS.Timeout | null = null;
      let finished = false; // Prevent double resolution/rejection

      const cleanupPwdListeners = (err?: Error) => {
        if (finished) return; // Already handled
        finished = true;
        if (pwdTimeoutId) clearTimeout(pwdTimeoutId);
        pwdTimeoutId = null;

        const stdoutListener = onPwdData; // Capture current reference
        const stderrListener = onPwdError; // Capture current reference
        onPwdData = null; // Nullify before removing
        onPwdError = null;

        if (this.bashProcess && !this.bashProcess.killed) {
          if (stdoutListener)
            this.bashProcess.stdout.removeListener('data', stdoutListener);
          if (stderrListener)
            this.bashProcess.stderr.removeListener('data', stderrListener);
        }

        if (err) {
          reject(err);
        } else {
          // Trim whitespace and trailing newlines robustly
          resolve(pwdOutput.trim());
        }
      };

      onPwdData = (data: Buffer) => {
        if (!onPwdData) return; // Listener removed
        const dataStr = data.toString();
        const delimiterIndex = dataStr.indexOf(pwdDelimiter);
        if (delimiterIndex !== -1) {
          pwdOutput += dataStr.substring(0, delimiterIndex);
          cleanupPwdListeners(); // Resolve successfully
        } else {
          pwdOutput += dataStr;
        }
      };

      onPwdError = (data: Buffer) => {
        if (!onPwdError) return; // Listener removed
        const dataStr = data.toString();
        // If delimiter appears on stderr, or any stderr occurs, treat as error
        console.error(`Error during PWD check: ${dataStr}`);
        cleanupPwdListeners(
          new Error(
            `Stderr received during pwd check: ${this.truncateOutput(dataStr, 100)}`,
          ),
        );
      };

      // Attach listeners
      this.bashProcess.stdout.on('data', onPwdData);
      this.bashProcess.stderr.on('data', onPwdError);

      // Set timeout
      pwdTimeoutId = setTimeout(() => {
        cleanupPwdListeners(new Error('Timeout waiting for pwd response'));
      }, 5000); // 5 second timeout for pwd

      // Write command
      try {
        // Use printf for robustness against special characters in PWD and ensure newline
        const pwdCommand = `printf "%s" "$PWD"; printf "${pwdDelimiter}";\n`;
        if (this.bashProcess?.stdin?.writable) {
          this.bashProcess.stdin.write(pwdCommand, (err) => {
            if (err) {
              // Error during write callback, likely means shell is unresponsive
              console.error('Error writing pwd command (callback):', err);
              cleanupPwdListeners(
                new Error(`Failed to write pwd command: ${err.message}`),
              );
            }
          });
        } else {
          throw new Error('Shell stdin not writable for pwd command.');
        }
      } catch (e: unknown) {
        console.error('Exception writing pwd command:', e);
        cleanupPwdListeners(
          new Error(`Exception writing pwd command: ${getErrorMessage(e)}`),
        );
      }
    });
  }

  // --- Truncate Output (unchanged) ---
  private truncateOutput(output: string, limit?: number): string {
    const effectiveLimit = limit ?? this.outputLimit;
    if (output.length > effectiveLimit) {
      return (
        output.substring(0, effectiveLimit) +
        `\n... [Output truncated at ${effectiveLimit} characters]`
      );
    }
    return output;
  }

  // --- Clear Queue (unchanged) ---
  private clearQueue(error: Error) {
    const queue = this.commandQueue;
    this.commandQueue = [];
    queue.forEach(({ resolve, params }) =>
      resolve({
        llmContent: `Command cancelled: ${params.command}\nReason: ${error.message}`,
        returnDisplay: `Command Cancelled: ${error.message}`,
      }),
    );
  }

  // --- Destroy (Added cleanup for pending background tasks if possible) ---
  destroy() {
    // Reject any pending shell readiness promise
    this.rejectShellReady?.(
      new Error('BashTool destroyed during initialization or operation.'),
    );
    this.rejectShellReady = undefined; // Prevent further calls
    this.resolveShellReady = undefined;

    this.clearQueue(new Error('BashTool is being destroyed.'));

    // Attempt to cleanup listeners for the *currently executing* command, if any
    try {
      this.currentCommandCleanup?.();
    } catch (e) {
      console.warn('Error during current command cleanup:', e);
    }

    // Handle the bash process itself
    if (this.bashProcess) {
      const proc = this.bashProcess; // Reference before nullifying
      const pid = proc.pid;
      this.bashProcess = null; // Nullify reference immediately

      proc.stdout?.removeAllListeners();
      proc.stderr?.removeAllListeners();
      proc.removeAllListeners('error');
      proc.removeAllListeners('close');

      // Ensure stdin is closed
      proc.stdin?.end();

      try {
        // Don't wait for these, just attempt
        proc.kill('SIGTERM'); // Attempt graceful first
        setTimeout(() => {
          if (!proc.killed) {
            proc.kill('SIGKILL'); // Force kill if needed
          }
        }, 500); // 500ms grace period
      } catch (e: unknown) {
        // Catch errors if process already exited etc.
        console.warn(
          `Error trying to kill bash process PID: ${pid}: ${getErrorMessage(e)}`,
        );
      }
    }

    // Note: We cannot reliably clean up temp files for background tasks
    // that were polling when destroy() was called without more complex state tracking.
    // OS should eventually clean /tmp, or implement a startup cleanup routine if needed.
  }
} // End of TerminalTool class