Assistant: remove directory structure tool (#10870)

Addresses #10721, reworking the changes from #10517. Removes
`getDirectoryStructure` in favor of a `directoriesOnly` argument to
`getProjectTree` to save on input tokens and reduce the total number of
tools.

The same examples from the PR that originally introduced the tool, this
time using `getProjectTree` with `directoriesOnly`. Efficiently
exploring the root:

<img width="1652" height="936" alt="Screenshot 2025-12-01 at 4 18 31 PM"
src="https://github.com/user-attachments/assets/d7d72268-e6bb-43a1-bb19-a35cf460e233"
/>

Navigating a folder that's excluded by default by noticing that results
were excluded and calling the tool again:

<img width="1538" height="922" alt="Screenshot 2025-12-01 at 4 24 26 PM"
src="https://github.com/user-attachments/assets/f7f76d8e-836a-4555-a0cc-d082d88df3ff"
/>

Seems like models can get just as much mileage out of this interface as
with the dedicated tool.

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#### New Features

- Assistant: combine directory structure tool with project tree tool
(#10721)

#### Bug Fixes

- N/A


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---------

Signed-off-by: Simon P. Couch <[email protected]>
Co-authored-by: sharon <[email protected]>

Author: simonpcouch

extensions/positron-assistant/package.json

@@ -754,7 +754,7 @@
       {
         "name": "getProjectTree",
         "displayName": "Get Project Tree",
-        "modelDescription": "Get the project tree of the current workspace as a JSON object. This is useful for understanding the structure of the project and finding files. Empty folders are not included in the tree.",
+        "modelDescription": "Get the project tree of the current workspace as a JSON object. This is useful for understanding the structure of the project and finding files. Empty folders are not included in the tree unless `directoriesOnly` is true. Set `directoriesOnly` to true to return only directories without listing files within them; this is more efficient for discovering directories.",
         "icon": "$(file-directory)",
         "toolReferenceName": "projectTree",
         "userDescription": "Get the project tree of the current workspace.",
@@ -787,73 +787,22 @@
               "description": "Whether to skip all automatic exclusions (.gitignore rules, VS Code exclude settings, and default exclusions for dependencies, build artifacts, and other commonly ignored files/directories). When true, only the explicit `exclude` patterns will be applied.",
               "default": false
             },
-            "maxFiles": {
+            "maxItems": {
               "type": "number",
-              "description": "The maximum number of files to include in the project tree (<=50). If this limit is reached, a compressed description of the project will be provided instead.",
+              "description": "The maximum number of items (files or directories) to include in the project tree (<=50). If this limit is reached, a compressed description of the project will be provided instead.",
               "default": 50
+            },
+            "directoriesOnly": {
+              "type": "boolean",
+              "description": "When true, returns only directories without listing files within them. Empty directories are included. This is more efficient for directory queries. Prefer this over running code in the terminal for finding directories.",
+              "default": false
             }
           },
           "required": [
             "include"
           ]
         }
       },
-      {
-        "name": "getDirectoryStructure",
-        "displayName": "Get Directory Structure",
-        "modelDescription": "Returns a list of directories without listing files within them. Empty directories are included. Unlike getProjectTree, this tool focuses on directories only and is more efficient for directory queries. Prefer this tool over running code in the terminal for finding directories.",
-        "icon": "$(folder)",
-        "toolReferenceName": "directoryStructure",
-        "userDescription": "Get the directory structure of the workspace.",
-        "canBeReferencedInPrompt": true,
-        "tags": [
-          "positron-assistant",
-          "requires-workspace"
-        ],
-        "inputSchema": {
-          "type": "object",
-          "properties": {
-            "path": {
-              "type": "string",
-              "description": "Starting path to explore (relative to workspace root). Defaults to workspace root if not specified."
-            },
-            "maxDepth": {
-              "type": "number",
-              "description": "Maximum recursion depth. 1 shows only immediate subdirectories. Must be between 1 and 3.",
-              "default": 1,
-              "minimum": 1,
-              "maximum": 3
-            },
-            "maxDirectories": {
-              "type": "number",
-              "description": "Maximum number of directories to return.",
-              "default": 50,
-              "maximum": 100
-            },
-            "include": {
-              "type": "array",
-              "items": {
-                "type": "string",
-                "description": "A glob pattern to include directories."
-              },
-              "description": "Glob patterns to include directories. Only directories matching these patterns will be returned."
-            },
-            "exclude": {
-              "type": "array",
-              "items": {
-                "type": "string",
-                "description": "A glob pattern to exclude directories."
-              },
-              "description": "Glob patterns to exclude directories. These patterns will be applied in addition to the default excludes unless `skipDefaultExcludes` is true."
-            },
-            "skipDefaultExcludes": {
-              "type": "boolean",
-              "description": "Whether to skip all automatic exclusions (.gitignore rules, VS Code exclude settings, and default exclusions for dependencies, build artifacts, and other commonly ignored directories). When true, only the explicit `exclude` patterns will be applied.",
-              "default": false
-            }
-          }
-        }
-      },
       {
         "name": "getChangedFiles",
         "displayName": "Get changed files",

extensions/positron-assistant/src/tools.ts

@@ -8,7 +8,6 @@ import * as positron from 'positron';
 import { ParticipantService } from './participants.js';
 import { PositronAssistantToolName } from './types.js';
 import { ProjectTreeTool } from './tools/projectTreeTool.js';
-import { DirectoryStructureTool } from './tools/directoryStructureTool.js';
 import { getWorkspaceGitChanges, GitRepoChangeKind } from './git.js';
 import { DocumentCreateTool } from './tools/documentCreate.js';
 import { registerNotebookTools } from './tools/notebookTools.js';
@@ -412,8 +411,6 @@ export function registerAssistantTools(
 
 	context.subscriptions.push(ProjectTreeTool);
 
-	context.subscriptions.push(DirectoryStructureTool);
-
 	context.subscriptions.push(DocumentCreateTool);
 
 	// Register notebook-specific tools for notebook participant