diff --git a/bugbug/tools/test_generation/__init__.py b/bugbug/tools/test_generation/__init__.py
new file mode 100644
index 0000000000..db567172b0
--- /dev/null
+++ b/bugbug/tools/test_generation/__init__.py
@@ -0,0 +1,12 @@
+# -*- coding: utf-8 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from bugbug.tools.test_generation.agent import TestGenerationTool
+from bugbug.tools.test_generation.data_types import TestGenerationResult
+
+__all__ = [
+    "TestGenerationResult",
+    "TestGenerationTool",
+]
diff --git a/bugbug/tools/test_generation/agent.py b/bugbug/tools/test_generation/agent.py
new file mode 100644
index 0000000000..dacf58f78b
--- /dev/null
+++ b/bugbug/tools/test_generation/agent.py
@@ -0,0 +1,114 @@
+# -*- coding: utf-8 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+"""Test case and test step generation tool implementation."""
+
+from __future__ import annotations
+
+from typing import Any
+
+from langchain.agents import create_agent
+from langchain.chat_models import BaseChatModel, init_chat_model
+from langchain.messages import HumanMessage
+
+from bugbug.tools.base import GenerativeModelTool
+from bugbug.tools.core.llms import DEFAULT_OPENAI_MODEL
+from bugbug.tools.test_generation.data_types import TestGenerationResult
+from bugbug.tools.test_generation.prompts import (
+    TEST_CASES_PROMPT_TEMPLATE,
+    TEST_STEPS_PROMPT_TEMPLATE,
+)
+
+
+def _message_content_to_text(content: Any) -> str:
+    if isinstance(content, str):
+        return content
+
+    if isinstance(content, list):
+        return "".join(
+            item.get("text", "")
+            for item in content
+            if isinstance(item, dict) and item.get("type") == "text"
+        )
+
+    return str(content)
+
+
+class TestGenerationTool(GenerativeModelTool):
+    """Tool for generating QA test cases and test steps."""
+
+    def __init__(
+        self,
+        llm: BaseChatModel,
+        target_software: str = "Mozilla Firefox",
+    ) -> None:
+        self.target_software = target_software
+        self.agent = create_agent(llm)
+
+    @classmethod
+    def create(cls, **kwargs):
+        """Factory method to instantiate the tool with default dependencies."""
+        if "llm" not in kwargs:
+            kwargs["llm"] = init_chat_model(DEFAULT_OPENAI_MODEL)
+
+        return cls(**kwargs)
+
+    def _invoke_llm(self, prompt: str) -> str:
+        result = self.agent.invoke({"messages": [HumanMessage(prompt)]})
+        return _message_content_to_text(result["messages"][-1].content).strip()
+
+    def generate_test_cases(
+        self,
+        feature_description: str,
+        test_scope: str,
+        qa_test_cases: str = "",
+    ) -> str:
+        """Generate missed test cases for a feature."""
+        prompt = TEST_CASES_PROMPT_TEMPLATE.format(
+            target_software=self.target_software,
+            feature_description=feature_description,
+            test_scope=test_scope,
+            qa_test_cases=qa_test_cases or "N/A",
+        )
+        return self._invoke_llm(prompt)
+
+    def generate_test_steps(
+        self,
+        feature_description: str,
+        test_cases: str,
+    ) -> str:
+        """Generate detailed test steps for each test case."""
+        prompt = TEST_STEPS_PROMPT_TEMPLATE.format(
+            target_software=self.target_software,
+            feature_description=feature_description,
+            test_cases=test_cases,
+        )
+        return self._invoke_llm(prompt)
+
+    def run(
+        self,
+        feature_description: str,
+        test_scope: str,
+        qa_test_cases: str = "",
+        generate_steps: bool = True,
+    ) -> TestGenerationResult:
+        """Generate test cases and optionally generate steps for them."""
+        generated_test_cases = self.generate_test_cases(
+            feature_description,
+            test_scope,
+            qa_test_cases,
+        )
+
+        test_steps = None
+        if generate_steps and generated_test_cases:
+            test_steps = self.generate_test_steps(
+                feature_description,
+                generated_test_cases,
+            )
+
+        return TestGenerationResult(
+            test_cases=generated_test_cases,
+            test_steps=test_steps,
+        )
diff --git a/bugbug/tools/test_generation/data_types.py b/bugbug/tools/test_generation/data_types.py
new file mode 100644
index 0000000000..806976f838
--- /dev/null
+++ b/bugbug/tools/test_generation/data_types.py
@@ -0,0 +1,12 @@
+# -*- coding: utf-8 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class TestGenerationResult:
+    test_cases: str
+    test_steps: str | None = None
diff --git a/bugbug/tools/test_generation/prompts.py b/bugbug/tools/test_generation/prompts.py
new file mode 100644
index 0000000000..f9b4ae32cd
--- /dev/null
+++ b/bugbug/tools/test_generation/prompts.py
@@ -0,0 +1,60 @@
+# -*- coding: utf-8 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+TEST_CASES_PROMPT_TEMPLATE = """You are an expert Quality Assurance Engineer with expertise in designing high level test cases for features of the {target_software} web browser.
+You are given a feature's description, its scope of testing, and a list of already existing test cases.
+Using the knowledge and information you are given, generate no more than 15 test cases that have been missed for the feature.
+
+-- This is the feature's description --:
+{feature_description}
+
+-- These are the existing test cases so far for the feature --:
+{qa_test_cases}
+
+-- This is the feature's scope of testing --:
+{test_scope}
+
+-- Here are some tips for success --:
+1. Thoroughly understand the feature from the description, scope of testing and the existing test cases.
+2. Alter the wording while generating test cases.
+3. Check to see if each generated case is relevant to the feature.
+4. Check to see if each generated case is within the scope of testing.
+5. Check to see if each generated case is dissimilar to any existing test cases.
+
+The test cases should be presented in a numbered list, with each entry being a single, concise test case.
+Avoid using a title and markdown formatting."""
+
+
+TEST_STEPS_PROMPT_TEMPLATE = """You are an expert Quality Assurance Engineer with expertise in designing detailed test steps for test cases of features of the {target_software} web browser.
+You are given a feature's description and a list of test cases.
+Using the knowledge and information you are given, generate test steps for each test case.
+
+-- This is the feature's description --:
+{feature_description}
+
+-- These are the test cases for the feature --:
+{test_cases}
+
+-- Here are some tips for success --:
+1. Thoroughly understand the feature from the description and the test cases.
+2. For each test case, generate clear and concise steps to execute the test case.
+3. Each test case should have its own set of steps.
+4. Present the steps in a numbered list under each test case.
+Avoid using a title and markdown formatting.
+
+-- Here are some examples --:
+Test Case 1: Ensure that Rich suggestions entries match the design
+Test Steps:
+1. Launch Firefox.
+2. Start typing a popular keyword inside the Address Bar.
+3. Observe the Rich entities icon and description.
+
+Test Case 2: Search-shortcut - Ensure that Rich entities are accessible via keyboard
+Test Steps:
+1. Launch Firefox.
+2. Observe the Address Bar.
+3. Click inside the Address Bar, select the google search shortcut.
+4. Press 'Down' arrow key.
+5. Navigate through the Rich entities using Up/Down arrow keys."""