diff --git a/.gitignore b/.gitignore
index 89ef3acf..f4a119d5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,4 +3,5 @@ venv/
 .ruff_cache/
 .vscode/
 .coverage
+config.json
 __pycache__/
\ No newline at end of file
diff --git a/prometheus/configuration/__init__.py b/prometheus/configuration/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/prometheus/configuration/config.py b/prometheus/configuration/config.py
new file mode 100644
index 00000000..6316c3d6
--- /dev/null
+++ b/prometheus/configuration/config.py
@@ -0,0 +1,12 @@
+import json
+from pathlib import Path
+
+CONFIG_FILE = Path(__file__).parent / "config.json"
+
+
+def load_config():
+  with open(CONFIG_FILE, "r") as f:
+    return json.load(f)
+
+
+config = load_config()
diff --git a/prometheus/configuration/example_config.json b/prometheus/configuration/example_config.json
new file mode 100644
index 00000000..9497f829
--- /dev/null
+++ b/prometheus/configuration/example_config.json
@@ -0,0 +1,12 @@
+{
+  "neo4j": {
+    "uri": "CHANGE_ME",
+    "username": "CHANGE_ME",
+    "password": "CHANGE_ME",
+    "database": "neo4j",
+    "batch_size": 1000
+  },
+  "knowledge_graph": {
+    "max_ast_depth": 5
+  }
+}
\ No newline at end of file
diff --git a/prometheus/graph/graph_types.py b/prometheus/graph/graph_types.py
index b60bed80..94dd0389 100644
--- a/prometheus/graph/graph_types.py
+++ b/prometheus/graph/graph_types.py
@@ -24,8 +24,8 @@ class ASTNode:
 
   Attributes:
     type: The tree-sitter node type.
-    start_line: The starting line number.
-    end_line: The ending line number.
+    start_line: The starting line number. 0-indexed and inclusive.
+    end_line: The ending line number.  0-indexed and inclusive.
     text: The source code correcpsonding to the node.
   """
 
@@ -79,7 +79,9 @@ def to_neo4j_node(self) -> Union["Neo4jFileNode", "Neo4jASTNode", "Neo4jTextNode
         )
       case TextNode():
         return Neo4jTextNode(
-          node_id=self.node_id, text=self.node.text, metadata=self.node.metadata
+          node_id=self.node_id,
+          text=self.node.text,
+          metadata=self.node.metadata,
         )
       case _:
         raise ValueError("Unknown KnowledgeGraphNode.node type")
@@ -122,23 +124,28 @@ def to_neo4j_edge(
     match self.type:
       case KnowledgeGraphEdgeType.has_file:
         return Neo4jHasFileEdge(
-          source=self.source.to_neo4j_node(), target=self.target.to_neo4j_node()
+          source=self.source.to_neo4j_node(),
+          target=self.target.to_neo4j_node(),
         )
       case KnowledgeGraphEdgeType.has_ast:
         return Neo4jHasASTEdge(
-          source=self.source.to_neo4j_node(), target=self.target.to_neo4j_node()
+          source=self.source.to_neo4j_node(),
+          target=self.target.to_neo4j_node(),
         )
       case KnowledgeGraphEdgeType.parent_of:
         return Neo4jParentOfEdge(
-          source=self.source.to_neo4j_node(), target=self.target.to_neo4j_node()
+          source=self.source.to_neo4j_node(),
+          target=self.target.to_neo4j_node(),
         )
       case KnowledgeGraphEdgeType.has_text:
         return Neo4jHasTextEdge(
-          source=self.source.to_neo4j_node(), target=self.target.to_neo4j_node()
+          source=self.source.to_neo4j_node(),
+          target=self.target.to_neo4j_node(),
         )
       case KnowledgeGraphEdgeType.next_chunk:
         return Neo4jNextChunkEdge(
-          source=self.source.to_neo4j_node(), target=self.target.to_neo4j_node()
+          source=self.source.to_neo4j_node(),
+          target=self.target.to_neo4j_node(),
         )
       case _:
         raise ValueError(f"Unknown edge type: {self.type}")
diff --git a/prometheus/graph/knowledge_graph.py b/prometheus/graph/knowledge_graph.py
index aca78cf1..41fbebbd 100644
--- a/prometheus/graph/knowledge_graph.py
+++ b/prometheus/graph/knowledge_graph.py
@@ -84,14 +84,16 @@ def _build_graph(self, root_dir: Path):
         for child_file in sorted(file.iterdir()):
           child_file_node = FileNode(
             basename=child_file.name,
-            relative_path=str(child_file.relative_to(root_dir)),
+            relative_path=str(child_file.relative_to(root_dir).as_posix()),
           )
           kg_child_file_node = KnowledgeGraphNode(self._next_node_id, child_file_node)
           self._next_node_id += 1
           self._knowledge_graph_nodes.append(kg_child_file_node)
           self._knowledge_graph_edges.append(
             KnowledgeGraphEdge(
-              kg_file_path_node, kg_child_file_node, KnowledgeGraphEdgeType.has_file
+              kg_file_path_node,
+              kg_child_file_node,
+              KnowledgeGraphEdgeType.has_file,
             )
           )
 
diff --git a/prometheus/tools/__init__.py b/prometheus/tools/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/prometheus/tools/graph_traversal.py b/prometheus/tools/graph_traversal.py
new file mode 100644
index 00000000..1ba7c054
--- /dev/null
+++ b/prometheus/tools/graph_traversal.py
@@ -0,0 +1,240 @@
+from pathlib import Path
+from pydantic import BaseModel, Field
+
+from neo4j import GraphDatabase
+
+from prometheus.parser import tree_sitter_parser
+from prometheus.utils import neo4j_util
+
+MAX_RESULT = 20
+
+###############################################################################
+#                          FileNode retrieval                                 #
+###############################################################################
+
+
+class FindFileNodeWithBasenameInput(BaseModel):
+  basename: str = Field("The basename of FileNode to search for")
+
+
+def find_file_node_with_basename(basename: str, driver: GraphDatabase.driver) -> str:
+  query = f"""
+      MATCH (f:FileNode {{ basename: '{basename}' }})
+      RETURN f AS FileNode
+      ORDER BY f.node_id
+      LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+class FindFileNodeWithRelativePathInput(BaseModel):
+  relative_path: str = Field("The relative_path of FileNode to search for")
+
+
+def find_file_node_with_relative_path(
+  relative_path: str, driver: GraphDatabase.driver
+) -> str:
+  query = f"""\
+    MATCH (f:FileNode {{ relative_path: '{relative_path}' }})
+    RETURN f AS FileNode
+    ORDER BY f.node_id
+    LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+###############################################################################
+#                          ASTNode retrieval                                  #
+###############################################################################
+
+
+class FindASTNodeWithTextInput(BaseModel):
+  text: str = Field("Search ASTNode that exactly contains this text.")
+
+
+def find_ast_node_with_text(text: str, driver: GraphDatabase.driver) -> str:
+  query = f"""\
+    MATCH (f:FileNode) -[:HAS_AST]-> (:ASTNode) -[:PARENT_OF*]-> (a:ASTNode)
+    WHERE a.text CONTAINS '{text}'
+    RETURN f as FileNode, a AS ASTNode
+    ORDER BY SIZE(a.text)
+    LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+class FindASTNodeWithTypeInput(BaseModel):
+  type: str = Field("Search ASTNode that has this tree-sitter node type.")
+
+
+def find_ast_node_with_type(type: str, driver: GraphDatabase.driver) -> str:
+  query = f"""\
+    MATCH (f:FileNode) -[:HAS_AST]-> (:ASTNode) -[:PARENT_OF*]-> (a:ASTNode {{ type: '{type}' }})
+    RETURN f as FileNode, a AS ASTNode
+    ORDER BY a.node_id
+    LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+class FindASTNodeWithTextInFileInput(BaseModel):
+  text: str = Field("Search ASTNode that exactly contains this text.")
+  basename: str = Field("The basename of FileNode to search ASTNode.")
+
+
+def find_ast_node_with_text_in_file(
+  text: str, basename: str, driver: GraphDatabase.driver
+) -> str:
+  query = f"""\
+    MATCH (f:FileNode) -[:HAS_AST]-> (:ASTNode) -[:PARENT_OF*]-> (a:ASTNode)
+    WHERE f.basename = '{basename}' AND a.text CONTAINS '{text}'
+    RETURN f as FileNode, a AS ASTNode
+    ORDER BY SIZE(a.text)
+    LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+class FindASTNodeWithTypeInFileInput(BaseModel):
+  type: str = Field("Search ASTNode with this tree-sitter node type.")
+  basename: str = Field("The basename of FileNode to search ASTNode.")
+
+
+def find_ast_node_with_type_in_file(
+  type: str, basename: str, driver: GraphDatabase.driver
+) -> str:
+  query = f"""\
+    MATCH (f:FileNode) -[:HAS_AST]-> (:ASTNode) -[:PARENT_OF*]-> (a:ASTNode)
+    WHERE f.basename = '{basename}' AND a.type = '{type}'
+    RETURN f as FileNode, a AS ASTNode
+    ORDER BY SIZE(a.text)
+    LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+class FindASTNodeWithTypeAndTextInput(BaseModel):
+  type: str = Field("Search ASTNode with this tree-sitter node type.")
+  text: str = Field("Search ASTNode that exactly contains this text.")
+
+
+def find_ast_node_with_type_and_text(
+  type: str, text: str, driver: GraphDatabase.driver
+) -> str:
+  query = f"""\
+    MATCH (f:FileNode) -[:HAS_AST]-> (:ASTNode) -[:PARENT_OF*]-> (a:ASTNode)
+    WHERE a.type = '{type}' AND a.text CONTAINS '{text}'
+    RETURN f as FileNode, a AS ASTNode
+    ORDER BY SIZE(a.text)
+    LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+###############################################################################
+#                          TextNode retrieval                                 #
+###############################################################################
+
+
+class FindTextNodeWithTextInput(BaseModel):
+  text: str = Field("Search TextNode that exactly contains this text.")
+
+
+def find_text_node_with_text(text: str, driver: GraphDatabase.driver) -> str:
+  query = f"""\
+    MATCH (f:FileNode) -[:HAS_TEXT]-> (t:TextNode)
+    WHERE t.text CONTAINS '{text}'
+    RETURN f as FileNode, t AS TextNode
+    ORDER BY t.node_id
+    LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+class FindTextNodeWithTextInFileInput(BaseModel):
+  text: str = Field("Search TextNode that exactly contains this text.")
+  basename: str = Field("The basename of FileNode to search TextNode.")
+
+
+def find_text_node_with_text_in_file(
+  text: str, basename: str, driver: GraphDatabase.driver
+) -> str:
+  query = f"""\
+    MATCH (f:FileNode) -[:HAS_TEXT]-> (t:TextNode)
+    WHERE f.basename = '{basename}' AND t.text CONTAINS '{text}'
+    RETURN f as FileNode, t AS TextNode
+    ORDER BY t.node_id
+    LIMIT {MAX_RESULT}
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+class GetNextTextNodeWithNodeIdInput(BaseModel):
+  node_id: int = Field("Get the next TextNode of this given node_id.")
+
+
+def get_next_text_node_with_node_id(node_id: str, driver: GraphDatabase.driver) -> str:
+  query = f"""\
+    MATCH (a:TextNode {{ node_id: {node_id} }}) -[:NEXT_CHUNK]-> (b:TextNode)
+    RETURN b as TextNode
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+###############################################################################
+#                                 Other                                       #
+###############################################################################
+
+
+class PreviewFileContentWithBasenameInput(BaseModel):
+  basename: str = Field("The basename of FileNode to preview.")
+
+
+def preview_file_content_with_basename(
+  basename: str, driver: GraphDatabase.driver
+) -> str:
+  source_code_query = f"""\
+    MATCH (f:FileNode {{ basename: '{basename}' }}) -[:HAS_AST]-> (a:ASTNode)
+    WITH f, apoc.text.split(a.text, '\\R') AS lines
+    RETURN f as FileNode, apoc.text.join(lines[0..300], '\\n') AS preview
+    ORDER BY f.node_id
+  """
+
+  text_query = f"""\
+    MATCH (f:FileNode {{ basename: '{basename}' }}) -[:HAS_TEXT]-> (t:TextNode)
+    WHERE NOT EXISTS((:TextNode) -[:NEXT_CHUNK]-> (t))
+    RETURN f as FileNode, t.text AS preview
+    ORDER BY f.node_id
+  """
+
+  if tree_sitter_parser.supports_file(Path(basename)):
+    return neo4j_util.run_neo4j_query(source_code_query, driver)
+  return neo4j_util.run_neo4j_query(text_query, driver)
+
+
+class GetParentNodeInput(BaseModel):
+  node_id: str = Field(description="Get parent node of node with this node_id")
+
+
+def get_parent_node(node_id: int, driver: GraphDatabase.driver) -> str:
+  query = f"""\
+    MATCH (p) -[r]-> (c {{ node_id: {node_id} }})
+    WHERE type(r) IN ['HAS_FILE', 'HAS_TEXT', 'HAS_AST', 'PARENT_OF']
+    RETURN p as ParentNode, head(labels(p)) as ParentNodeType
+    ORDER BY p.node_id 
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
+
+
+class GetChildrenNodeInput(BaseModel):
+  node_id: str = Field(description="Get children nodes of node with this node_id")
+
+
+def get_children_node(node_id: int, driver: GraphDatabase.driver) -> str:
+  query = f"""\
+    MATCH (p {{ node_id: {node_id} }}) -[r]-> (c)
+    WHERE type(r) IN ['HAS_FILE', 'HAS_TEXT', 'HAS_AST', 'PARENT_OF']
+    RETURN c as ChildNode, head(labels(p)) as ChildNodeType
+    ORDER BY c.node_id 
+  """
+  return neo4j_util.run_neo4j_query(query, driver)
diff --git a/prometheus/utils/__init__.py b/prometheus/utils/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/prometheus/utils/neo4j_util.py b/prometheus/utils/neo4j_util.py
new file mode 100644
index 00000000..f4ff144d
--- /dev/null
+++ b/prometheus/utils/neo4j_util.py
@@ -0,0 +1,39 @@
+import neo4j
+
+
+def format_neo4j_result(result: neo4j.Result) -> str:
+  """Format a Neo4j result into a string.
+
+  Args:
+    result: The result from a Neo4j query.
+
+  Returns:
+    A string representation of the result.
+  """
+  data = result.data()
+  output = ""
+  for index, row_result in enumerate(data):
+    output += f"Result {index+1}:\n"
+    for key in sorted(row_result.keys()):
+      output += f"{key}: {row_result[key]}\n"
+    output += "\n\n"
+  return output.strip()
+
+
+def run_neo4j_query(query: str, driver: neo4j.GraphDatabase.driver) -> str:
+  """Run a read-only Neo4j query and format the result into a string.
+
+  Args:
+    query: The query to run.
+    driver: The Neo4j driver to use.
+
+  Returns:
+    A string representation of the result.
+  """
+
+  def query_transaction(tx):
+    result = tx.run(query)
+    return format_neo4j_result(result)
+
+  with driver.session() as session:
+    return session.execute_read(query_transaction)
diff --git a/tests/graph/test_knowledge_graph.py b/tests/graph/test_knowledge_graph.py
index 86db20d0..e46419b4 100644
--- a/tests/graph/test_knowledge_graph.py
+++ b/tests/graph/test_knowledge_graph.py
@@ -5,17 +5,17 @@
 def test_build_graph():
   knowledge_graph = KnowledgeGraph(test_project_paths.TEST_PROJECT_PATH, 1000)
 
-  assert knowledge_graph._next_node_id == 97
+  assert knowledge_graph._next_node_id == 96
   # 8 FileNode
-  # 85 ASTnode
+  # 84 ASTnode
   # 4 TextNode
-  assert len(knowledge_graph._knowledge_graph_nodes) == 97
-  assert len(knowledge_graph._knowledge_graph_edges) == 99
+  assert len(knowledge_graph._knowledge_graph_nodes) == 96
+  assert len(knowledge_graph._knowledge_graph_edges) == 98
 
   assert len(knowledge_graph.get_file_nodes()) == 8
-  assert len(knowledge_graph.get_ast_nodes()) == 85
+  assert len(knowledge_graph.get_ast_nodes()) == 84
   assert len(knowledge_graph.get_text_nodes()) == 4
-  assert len(knowledge_graph.get_parent_of_edges()) == 82
+  assert len(knowledge_graph.get_parent_of_edges()) == 81
   assert len(knowledge_graph.get_has_file_edges()) == 7
   assert len(knowledge_graph.get_has_ast_edges()) == 3
   assert len(knowledge_graph.get_has_text_edges()) == 4
diff --git a/tests/neo4j/test_handler.py b/tests/neo4j/test_handler.py
index 8a0b3bea..615a802f 100644
--- a/tests/neo4j/test_handler.py
+++ b/tests/neo4j/test_handler.py
@@ -15,9 +15,10 @@
 @pytest.fixture(scope="session")
 def setup_neo4j_container():
   kg = KnowledgeGraph(test_project_paths.TEST_PROJECT_PATH, 1000)
-  with Neo4jContainer(
+  container = Neo4jContainer(
     image=NEO4J_IMAGE, username=NEO4J_USERNAME, password=NEO4J_PASSWORD
-  ) as neo4j_container:
+  ).with_env("NEO4JLABS_PLUGINS", '["apoc"]')
+  with container as neo4j_container:
     uri = neo4j_container.get_connection_url()
     handler = Handler(uri, NEO4J_USERNAME, NEO4J_PASSWORD, "neo4j", 100)
     handler.write_knowledge_graph(kg)
@@ -40,7 +41,7 @@ def _count_num_ast_nodes(tx):
   with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
     with driver.session() as session:
       read_ast_nodes = session.execute_read(_count_num_ast_nodes)
-      assert len(read_ast_nodes) == 85
+      assert len(read_ast_nodes) == 84
 
 
 def test_num_file_nodes(setup_neo4j_container):
@@ -94,7 +95,7 @@ def _count_num_parent_of_edges(tx):
   with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
     with driver.session() as session:
       read_parent_of_edges = session.execute_read(_count_num_parent_of_edges)
-      assert len(read_parent_of_edges) == 82
+      assert len(read_parent_of_edges) == 81
 
 
 def test_num_has_file_edges(setup_neo4j_container):
diff --git a/tests/test_project/test.c b/tests/test_project/test.c
index 822faf74..79a11609 100644
--- a/tests/test_project/test.c
+++ b/tests/test_project/test.c
@@ -1,6 +1,6 @@
 #include <stdio.h>
 
 int main() {
-    printf("Hello world!\n");
+    printf("Hello world!");
     return 0;
 }
\ No newline at end of file
diff --git a/tests/tools/__init__.py b/tests/tools/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/tools/test_graph_traversal.py b/tests/tools/test_graph_traversal.py
new file mode 100644
index 00000000..027e6faf
--- /dev/null
+++ b/tests/tools/test_graph_traversal.py
@@ -0,0 +1,322 @@
+from neo4j import GraphDatabase
+import pytest
+
+from testcontainers.neo4j import Neo4jContainer
+
+from prometheus.graph.knowledge_graph import KnowledgeGraph
+from prometheus.neo4j.handler import Handler
+from prometheus.tools import graph_traversal
+from tests.test_utils import test_project_paths
+
+NEO4J_IMAGE = "neo4j:5.20.0"
+NEO4J_USERNAME = "neo4j"
+NEO4J_PASSWORD = "password"
+
+
+@pytest.fixture(scope="session")
+def setup_neo4j_container():
+  kg = KnowledgeGraph(test_project_paths.TEST_PROJECT_PATH, 1000)
+  container = Neo4jContainer(
+    image=NEO4J_IMAGE, username=NEO4J_USERNAME, password=NEO4J_PASSWORD
+  ).with_env("NEO4JLABS_PLUGINS", '["apoc"]')
+  with container as neo4j_container:
+    uri = neo4j_container.get_connection_url()
+    handler = Handler(uri, NEO4J_USERNAME, NEO4J_PASSWORD, "neo4j", 100)
+    handler.write_knowledge_graph(kg)
+    handler.close()
+    yield neo4j_container
+
+
+def test_find_file_node_with_basename(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_file_node_with_basename(
+      test_project_paths.PYTHON_FILE.name, driver
+    )
+
+  basename = test_project_paths.PYTHON_FILE.name
+  relative_path = str(
+    test_project_paths.PYTHON_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert result.count("FileNode") == 1
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+
+
+def test_find_file_node_with_relative_path(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  relative_path = str(
+    test_project_paths.MD_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_file_node_with_relative_path(relative_path, driver)
+
+  basename = test_project_paths.MD_FILE.name
+  assert result.count("FileNode") == 1
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+
+
+def test_find_ast_node_with_text(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  text = "System.out.println"
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_ast_node_with_text(text, driver)
+
+  assert "FileNode" in result
+  assert "ASTNode" in result
+
+  basename = test_project_paths.JAVA_FILE.name
+  relative_path = str(
+    test_project_paths.JAVA_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert "'text': 'System.out.println(\"Hello world!\")'" in result
+  assert "'type': 'method_invocation'" in result
+  assert "'start_line': 2" in result
+  assert "'end_line': 2" in result
+
+
+def test_find_ast_node_with_type(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  type = "argument_list"
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_ast_node_with_type(type, driver)
+
+  assert "FileNode" in result
+  assert "ASTNode" in result
+
+  basename = test_project_paths.JAVA_FILE.name
+  relative_path = str(
+    test_project_paths.JAVA_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert "'text': '(\"Hello world!\")'" in result
+  assert f"'type': '{type}'" in result
+  assert "'start_line': 2" in result
+  assert "'end_line': 2" in result
+
+
+def test_find_ast_node_with_text_in_file(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  text = "printf"
+  basename = test_project_paths.C_FILE.name
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_ast_node_with_text_in_file(text, basename, driver)
+
+  relative_path = str(
+    test_project_paths.C_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert f"'text': '{text}'" in result
+  assert "'type': 'identifier'" in result
+  assert "'start_line': 3" in result
+  assert "'end_line': 3" in result
+
+
+def test_find_ast_node_with_type_in_file(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  type = "string_literal"
+  basename = test_project_paths.C_FILE.name
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_ast_node_with_type_in_file(type, basename, driver)
+
+  relative_path = str(
+    test_project_paths.C_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert "'text': '\"Hello world!\"'" in result
+  assert f"'type': '{type}'" in result
+  assert "'start_line': 3" in result
+  assert "'end_line': 3" in result
+
+
+def test_find_ast_node_with_type_and_text(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  type = "string_literal"
+  text = "Hello world!"
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_ast_node_with_type_and_text(type, text, driver)
+
+  basename = test_project_paths.C_FILE.name
+  relative_path = str(
+    test_project_paths.C_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert f"'text': '\"{text}\"'" in result
+  assert f"'type': '{type}'" in result
+  assert "'start_line': 3" in result
+  assert "'end_line': 3" in result
+
+
+def test_find_text_node_with_text(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  text = "Text under header A."
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_text_node_with_text(text, driver)
+
+  assert "FileNode" in result
+  assert "TextNode" in result
+
+  basename = test_project_paths.MD_FILE.name
+  relative_path = str(
+    test_project_paths.MD_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert f"'text': '{text}'" in result
+  assert "'metadata': \"{'Header 1': 'A'}\"" in result
+
+
+def test_find_text_node_with_text_in_file(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  text = "Text under header B."
+  basename = test_project_paths.MD_FILE.name
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.find_text_node_with_text_in_file(text, basename, driver)
+
+  assert "FileNode" in result
+  assert "TextNode" in result
+
+  relative_path = str(
+    test_project_paths.MD_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert f"'text': '{text}'" in result
+  assert "'metadata': \"{'Header 1': 'A', 'Header 2': 'B'}\"" in result
+
+
+def test_get_next_text_node_with_node_id(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  # node_id of TextNode 'Text under header B.'
+  node_id = 36
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.get_next_text_node_with_node_id(node_id, driver)
+
+  assert "'text': 'Text under header C.'" in result
+  assert "'metadata': \"{'Header 1': 'A', 'Header 2': 'C'}\"" in result
+
+
+def test_preview_source_code_file_content_with_basename(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  basename = test_project_paths.C_FILE.name
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.preview_file_content_with_basename(basename, driver)
+
+  assert "FileNode" in result
+  assert "preview" in result
+
+  source_code = test_project_paths.C_FILE.open().read()
+  basename = test_project_paths.C_FILE.name
+  relative_path = str(
+    test_project_paths.C_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert source_code in result
+
+
+def test_preview_text_file_content_with_basename(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  basename = test_project_paths.MD_FILE.name
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.preview_file_content_with_basename(basename, driver)
+
+  assert "FileNode" in result
+  assert "preview" in result
+
+  basename = test_project_paths.MD_FILE.name
+  relative_path = str(
+    test_project_paths.MD_FILE.relative_to(
+      test_project_paths.TEST_PROJECT_PATH
+    ).as_posix()
+  )
+  assert f"'basename': '{basename}'" in result
+  assert f"'relative_path': '{relative_path}'" in result
+  assert "Text under header A." in result
+
+
+def test_get_parent_node(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  node_id = 30
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.get_parent_node(node_id, driver)
+
+  assert "ParentNode" in result
+  assert "ASTNode" in result
+
+  assert "'start_line': 2" in result
+  assert "'end_line': 2" in result
+  assert "'type': 'parameter_list'" in result
+  assert "'text': '()'" in result
+
+
+def test_get_children_node(setup_neo4j_container):
+  neo4j_container = setup_neo4j_container
+  uri = neo4j_container.get_connection_url()
+
+  node_id = 20
+  with GraphDatabase.driver(uri, auth=(NEO4J_USERNAME, NEO4J_PASSWORD)) as driver:
+    result = graph_traversal.get_children_node(node_id, driver)
+
+  assert "ChildNode" in result
+  assert "ASTNode" in result
+
+  assert result.count("Result") == 3
+
+  assert "'start_line': 3" in result
+  assert "'end_line': 3" in result
+  assert "'type': 'string_literal'" in result
+  assert "'text': '\"Hello world!\"'" in result