[MCP Server] Truncate output in execution tools

GitOrigin-RevId: 429d3e6ff370d9f9d341906a641bb83385be9387

plugins/mcp-server/src/com/intellij/mcpserver/toolsets/Constants.kt

@@ -1,9 +1,15 @@
 package com.intellij.mcpserver.toolsets
 
+import com.intellij.mcpserver.util.TruncateMode
+
 object Constants {
   const val RELATIVE_PATH_IN_PROJECT_DESCRIPTION: String = "Path relative to the project root"
   const val TIMEOUT_MILLISECONDS_DESCRIPTION: String = "Timeout in milliseconds"
   const val LONG_TIMEOUT_MILLISECONDS_VALUE: Int = 60 * 1000
   const val MEDIUM_TIMEOUT_MILLISECONDS_VALUE: Int = 10 * 1000
   const val SHORT_TIMEOUT_MILLISECONDS_VALUE: Int = 1 * 1000
+  const val MAX_LINES_COUNT_DESCRIPTION: String = "Maximum number of lines to return"
+  const val MAX_LINES_COUNT_VALUE: Int = 1000
+  const val TRUNCATE_MODE_DESCRIPTION: String = "How to truncate the text: from the start, in the middle, at the end, or don't truncate at all"
+  val TRUCATE_MODE_VALUE: TruncateMode = TruncateMode.START
 }

plugins/mcp-server/src/com/intellij/mcpserver/toolsets/general/ExecutionToolset.kt

@@ -19,7 +19,9 @@ import com.intellij.mcpserver.annotations.McpTool
 import com.intellij.mcpserver.mcpFail
 import com.intellij.mcpserver.project
 import com.intellij.mcpserver.toolsets.Constants
+import com.intellij.mcpserver.util.TruncateMode
 import com.intellij.mcpserver.util.checkUserConfirmationIfNeeded
+import com.intellij.mcpserver.util.truncateText
 import com.intellij.openapi.application.EDT
 import com.intellij.openapi.application.readAction
 import com.intellij.openapi.util.Key
@@ -71,6 +73,10 @@ class ExecutionToolset : McpToolset {
     configurationName: String,
     @McpDescription(Constants.TIMEOUT_MILLISECONDS_DESCRIPTION)
     timeout: Int = Constants.LONG_TIMEOUT_MILLISECONDS_VALUE,
+    @McpDescription(Constants.MAX_LINES_COUNT_DESCRIPTION)
+    maxLinesCount: Int = Constants.MAX_LINES_COUNT_VALUE,
+    @McpDescription(Constants.TRUNCATE_MODE_DESCRIPTION)
+    truncateMode: TruncateMode = Constants.TRUCATE_MODE_VALUE,
     ): RunConfigurationResult {
     val project = currentCoroutineContext().project
     val runManager = RunManager.getInstance(project)
@@ -128,10 +134,11 @@ class ExecutionToolset : McpToolset {
     val exitCode = withTimeoutOrNull(timeout.milliseconds) {
       exitCodeDeferred.await()
     }
+    val output = truncateText(outputBuilder.toString(), maxLinesCount = maxLinesCount, truncateMode = truncateMode)
     return RunConfigurationResult(
       exitCode = exitCode,
       timedOut = exitCode == null,
-      output = outputBuilder.toString()
+      output = output
     )
   }
 

plugins/mcp-server/src/com/intellij/mcpserver/toolsets/terminal/TerminalToolset.kt

@@ -8,6 +8,7 @@ import com.intellij.mcpserver.annotations.McpDescription
 import com.intellij.mcpserver.annotations.McpTool
 import com.intellij.mcpserver.project
 import com.intellij.mcpserver.toolsets.Constants
+import com.intellij.mcpserver.util.TruncateMode
 import com.intellij.mcpserver.util.checkUserConfirmationIfNeeded
 import com.intellij.openapi.diagnostic.logger
 import com.intellij.openapi.wm.ToolWindowManager
@@ -16,14 +17,11 @@ import kotlinx.serialization.EncodeDefault
 import kotlinx.serialization.ExperimentalSerializationApi
 import kotlinx.serialization.Serializable
 import org.jetbrains.plugins.terminal.TerminalToolWindowFactory
-import kotlin.time.Duration.Companion.minutes
+import kotlin.time.Duration.Companion.milliseconds
 
 private val logger = logger<TerminalToolset>()
 
 class TerminalToolset : McpToolset {
-  private val maxLineCount = 2000
-  private val timeout = 2.minutes
-
   @McpTool
   @McpDescription("""
         Executes a specified shell command in the IDE's integrated terminal.
@@ -42,17 +40,18 @@ class TerminalToolset : McpToolset {
   suspend fun execute_terminal_command(
     @McpDescription("Shell command to execute")
     command: String,
-
     @McpDescription("""Whether to execute the command in a default user's shell (bash, zsh, etc.). 
       |Useful if the command is not a commandline but a shell script, or if it's important to preserve real environment of the user's terminal. 
       |In the case of 'false' value the command will be started as a process""")
-    execute_in_shell: Boolean = false,
-
+    executeInShell: Boolean = false,
     @McpDescription("Whether to reuse an existing terminal window. Allows to avoid creating multiple terminals")
-    reuse_existing_terminal_window: Boolean = true,
-
+    reuseExistingTerminalWindow: Boolean = true,
     @McpDescription(Constants.TIMEOUT_MILLISECONDS_DESCRIPTION)
-    timeout_milliseconds: Int = Constants.LONG_TIMEOUT_MILLISECONDS_VALUE,
+    timeout: Int = Constants.LONG_TIMEOUT_MILLISECONDS_VALUE,
+    @McpDescription(Constants.MAX_LINES_COUNT_DESCRIPTION)
+    maxLinesCount: Int = Constants.MAX_LINES_COUNT_VALUE,
+    @McpDescription(Constants.TRUNCATE_MODE_DESCRIPTION)
+    truncateMode: TruncateMode = Constants.TRUCATE_MODE_VALUE,
   ): CommandExecutionResult {
     val project = currentCoroutineContext().project
     checkUserConfirmationIfNeeded(McpServerBundle.message("label.do.you.want.to.execute.command.in.terminal"), command, project)
@@ -60,7 +59,15 @@ class TerminalToolset : McpToolset {
     // TODO pass from http request later (MCP Client name or something else)
     val id = "mcp_session"
     val window = ToolWindowManager.getInstance(project).getToolWindow(TerminalToolWindowFactory.TOOL_WINDOW_ID)
-    return executeShellCommand(window = window, project = project, command = command, executeInShell = execute_in_shell, sessionId = if (reuse_existing_terminal_window) id else null, timeout = timeout)
+    return executeShellCommand(window = window,
+                               project = project,
+                               command = command,
+                               executeInShell = executeInShell,
+                               sessionId = if (reuseExistingTerminalWindow) id else null,
+                               timeout = Constants.LONG_TIMEOUT_MILLISECONDS_VALUE.milliseconds,
+                               maxLinesCount = maxLinesCount,
+                               truncateMode = truncateMode
+    )
   }
 
   @OptIn(ExperimentalSerializationApi::class)

plugins/mcp-server/src/com/intellij/mcpserver/toolsets/terminal/terminalToolsetUtil.kt

@@ -9,6 +9,8 @@ import com.intellij.execution.process.ProcessOutputTypes
 import com.intellij.mcpserver.McpServerBundle
 import com.intellij.mcpserver.mcpFail
 import com.intellij.mcpserver.toolsets.terminal.TerminalToolset.CommandExecutionResult
+import com.intellij.mcpserver.util.TruncateMode
+import com.intellij.mcpserver.util.truncateText
 import com.intellij.openapi.application.EDT
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.util.Key
@@ -28,7 +30,16 @@ import kotlin.time.Duration
 class CommandSession(val sessionId: String, val console: TerminalExecutionConsole)
 val MCP_TERMINAL_KEY: Key<CommandSession> = Key.create("MCP_TERMINAL_KEY")
 
-suspend fun executeShellCommand(window: ToolWindow?, project: Project, command: String, executeInShell: Boolean, sessionId: String?, timeout: Duration): CommandExecutionResult {
+suspend fun executeShellCommand(
+  window: ToolWindow?,
+  project: Project,
+  command: String,
+  executeInShell: Boolean,
+  sessionId: String?,
+  timeout: Duration,
+  maxLinesCount: Int,
+  truncateMode: TruncateMode = TruncateMode.START,
+): CommandExecutionResult {
   val defaultShell = ShConfigurationType.getDefaultShell(project)
 
   val commandLine = if (executeInShell) {
@@ -95,8 +106,9 @@ suspend fun executeShellCommand(window: ToolWindow?, project: Project, command:
   val exitCodeValue = withTimeoutOrNull(timeout) {
     exitCode.await()
   }
+  val truncateText = truncateText(text = output.toString(), maxLinesCount = maxLinesCount, truncateMode = truncateMode)
   if (exitCodeValue == null) {
-    return CommandExecutionResult(is_timed_out = true, command_output = output.toString())
+    return CommandExecutionResult(is_timed_out = true, command_output = truncateText)
   }
-  return CommandExecutionResult(command_exit_code = exitCodeValue, command_output = output.toString())
+  return CommandExecutionResult(command_exit_code = exitCodeValue, command_output = truncateText)
 }