fix: reviews failing to call next tool

utils/instructions.ts

@@ -107,8 +107,11 @@ function getShellInstructions(
   }
 }
 
-function getFileInstructions(): string {
-  return `### File operations\n\nUse your native file read/write/edit tools for all file operations.`;
+function getFileInstructions(shell: ResolvedPayload["shell"]): string {
+  if (shell === "disabled") {
+    return `### File operations\n\nShell is disabled — you cannot read arbitrary files. Use the diff content returned by MCP tools directly.`;
+  }
+  return `### File operations\n\nUse the \`shell\` MCP tool for all file operations. Examples:\n- Read a file: \`shell({ command: 'cat /path/to/file', description: 'read file' })\`\n- Read specific lines: \`shell({ command: 'sed -n "<start>,<end>p" /path/to/file', description: 'read lines' })\`\n- Search in a file: \`shell({ command: 'grep -n "pattern" /path/to/file', description: 'search' })\``;
 }
 
 function getStandaloneModeInstructions(
@@ -241,7 +244,7 @@ Use MCP tools from ${shockbotMcpName} for all Gitea operations. Never use the \`
 
 ${getShellInstructions(ctx.payload.shell, t)}
 
-${getFileInstructions()}
+${getFileInstructions(ctx.payload.shell)}
 
 ${getStandaloneModeInstructions(ctx.payload.event.trigger, t, ctx.outputSchema)}