diff --git a/server/galaxyls/server.py b/server/galaxyls/server.py
index cc38831..90e2657 100644
--- a/server/galaxyls/server.py
+++ b/server/galaxyls/server.py
@@ -22,6 +22,8 @@
     DocumentFormattingParams,
     DocumentLink,
     DocumentLinkParams,
+    DocumentSymbol,
+    DocumentSymbolParams,
     Hover,
     INITIALIZED,
     InitializeParams,
@@ -34,6 +36,7 @@
     TEXT_DOCUMENT_DID_OPEN,
     TEXT_DOCUMENT_DID_SAVE,
     TEXT_DOCUMENT_DOCUMENT_LINK,
+    TEXT_DOCUMENT_DOCUMENT_SYMBOL,
     TEXT_DOCUMENT_FORMATTING,
     TEXT_DOCUMENT_HOVER,
     TextDocumentIdentifier,
@@ -198,6 +201,16 @@ def process_code_actions(server: GalaxyToolsLanguageServer, params: CodeActionPa
     return server.service.get_available_refactoring_actions(xml_document, params)
 
 
+@language_server.feature(TEXT_DOCUMENT_DOCUMENT_SYMBOL)
+def document_symbol(server: GalaxyToolsLanguageServer, params: DocumentSymbolParams) -> Optional[List[DocumentSymbol]]:
+    """Returns a list of symbols defined in the document."""
+    document = _get_valid_document(server, params.text_document.uri)
+    if document:
+        xml_document = _get_xml_document(document)
+        return server.service.symbols_provider.get_document_symbols(xml_document)
+    return None
+
+
 @language_server.command(Commands.AUTO_CLOSE_TAGS)
 def auto_close_tag(server: GalaxyToolsLanguageServer, parameters: CommandParameters) -> Optional[AutoCloseTagResult]:
     """Responds to a close tag request to close the currently opened node."""
diff --git a/server/galaxyls/services/language.py b/server/galaxyls/services/language.py
index 47baff3..359f4fc 100644
--- a/server/galaxyls/services/language.py
+++ b/server/galaxyls/services/language.py
@@ -26,6 +26,7 @@
 from galaxyls.services.definitions import DocumentDefinitionsProvider
 from galaxyls.services.links import DocumentLinksProvider
 from galaxyls.services.macros import MacroExpanderService
+from galaxyls.services.symbols import DocumentSymbolsProvider
 from galaxyls.services.tools.common import (
     TestsDiscoveryService,
     ToolParamAttributeSorter,
@@ -75,6 +76,7 @@ def __init__(self) -> None:
         self.linter = GalaxyToolLinter()
         self.definitions_provider: Optional[DocumentDefinitionsProvider] = None
         self.link_provider = DocumentLinksProvider()
+        self.symbols_provider = DocumentSymbolsProvider()
 
     def set_workspace(self, workspace: Workspace) -> None:
         macro_definitions_provider = MacroDefinitionsProvider(workspace)
diff --git a/server/galaxyls/services/symbols.py b/server/galaxyls/services/symbols.py
new file mode 100644
index 0000000..914fd85
--- /dev/null
+++ b/server/galaxyls/services/symbols.py
@@ -0,0 +1,73 @@
+from typing import (
+    List,
+    Optional,
+)
+
+from lsprotocol.types import (
+    DocumentSymbol,
+    SymbolKind,
+)
+
+from galaxyls.services.xml.document import XmlDocument
+from galaxyls.services.xml.nodes import (
+    XmlAttribute,
+    XmlElement,
+    XmlSyntaxNode,
+)
+from galaxyls.services.xml.utils import convert_document_offsets_to_range
+
+
+class DocumentSymbolsProvider:
+    """Provides symbols defined in the tool document."""
+
+    def get_document_symbols(self, xml_document: XmlDocument) -> List[DocumentSymbol]:
+        """Gets all symbols defined in the tool document in a hierarchical structure."""
+        if xml_document.root is None:
+            return []
+        return [self._get_element_symbol_definition(xml_document, xml_document.root)]
+
+    def _get_element_children_symbols(self, element: XmlElement, xml_document: XmlDocument) -> List[DocumentSymbol]:
+        result: List[DocumentSymbol] = []
+        for child in element.children:
+            if isinstance(child, XmlAttribute):
+                result.append(self._get_attribute_symbol_definition(xml_document, child))
+            if isinstance(child, XmlElement):
+                result.append(self._get_element_symbol_definition(xml_document, child))
+        return result
+
+    def _get_element_symbol_definition(self, xml_document: XmlDocument, element: XmlElement) -> DocumentSymbol:
+        element_range = convert_document_offsets_to_range(xml_document.document, element.start, element.end)
+        return DocumentSymbol(
+            name=self._get_node_name(element),
+            kind=SymbolKind.Field,
+            detail=self._get_element_symbol_detail(element, xml_document),
+            range=element_range,
+            selection_range=element_range,
+            children=self._get_element_children_symbols(element, xml_document),
+        )
+
+    def _get_attribute_symbol_definition(self, xml_document: XmlDocument, attribute: XmlAttribute) -> DocumentSymbol:
+        attribute_range = convert_document_offsets_to_range(xml_document.document, attribute.start, attribute.end)
+        return DocumentSymbol(
+            name=self._get_node_name(attribute),
+            kind=SymbolKind.Property,
+            detail=attribute.value.unquoted if attribute.value else None,
+            range=attribute_range,
+            selection_range=attribute_range,
+        )
+
+    def _get_node_name(self, node: XmlSyntaxNode) -> str:
+        return node.name or ""
+
+    def _get_element_symbol_detail(self, element: XmlElement, xml_document: XmlDocument) -> Optional[str]:
+        if element.name in ["option", "when", "add", "remove"]:
+            detail = element.get_attribute_value("value")
+        elif element.name in ["citation", "validator"]:
+            detail = element.get_attribute_value("type")
+        elif element.name in ["requirement", "import"]:
+            detail = element.get_content(xml_document.document.source)
+        elif element.name in ["expand"]:
+            detail = element.get_attribute_value("macro")
+        else:
+            detail = element.get_attribute_value("id") or element.get_attribute_value("name")
+        return detail
diff --git a/server/galaxyls/tests/unit/test_symbols.py b/server/galaxyls/tests/unit/test_symbols.py
new file mode 100644
index 0000000..0cfd128
--- /dev/null
+++ b/server/galaxyls/tests/unit/test_symbols.py
@@ -0,0 +1,44 @@
+from galaxyls.services.symbols import DocumentSymbolsProvider
+from galaxyls.tests.unit.utils import TestUtils
+
+FIELD_SYMBOL_KIND = 8  # SymbolKind.Field
+PROPERTY_SYMBOL_KIND = 7  # SymbolKind.Property
+
+
+def test_get_document_symbols():
+    xml_document = TestUtils.from_source_to_xml_document("<tool></tool>")
+    provider = DocumentSymbolsProvider()
+    symbols = provider.get_document_symbols(xml_document)
+    assert len(symbols) == 1
+    assert symbols[0].name == "tool"
+    assert symbols[0].kind == FIELD_SYMBOL_KIND
+    assert len(symbols[0].children) == 0
+
+
+def test_get_element_children_symbols():
+    xml_document = TestUtils.from_source_to_xml_document("<tool><command></command></tool>")
+    provider = DocumentSymbolsProvider()
+    symbols = provider.get_document_symbols(xml_document)
+    element_symbol = symbols[0]
+    children_symbols = element_symbol.children
+    assert len(children_symbols) == 1
+    assert children_symbols[0].name == "command"
+    assert children_symbols[0].kind == FIELD_SYMBOL_KIND
+
+
+def test_get_attribute_symbol_definition():
+    xml_document = TestUtils.from_source_to_xml_document("<tool><command executable='true'></command></tool>")
+    provider = DocumentSymbolsProvider()
+    symbols = provider.get_document_symbols(xml_document)
+    attribute_symbol = symbols[0].children[0].children[0]
+    assert attribute_symbol.name == "executable"
+    assert attribute_symbol.kind == PROPERTY_SYMBOL_KIND
+
+
+def test_get_element_symbol_detail():
+    xml_document = TestUtils.from_source_to_xml_document('<tool id="TEST"></tool>')
+    provider = DocumentSymbolsProvider()
+    symbols = provider.get_document_symbols(xml_document)
+    assert len(symbols) == 1
+    element_symbol = symbols[0]
+    assert element_symbol.detail == "TEST"