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opik-optimizer
Advanced tools
The Opik Agent Optimizer refines your prompts to achieve better performance from your Large Language Models (LLMs). It supports a variety of optimization algorithms, all with a standardized API for consistent usage and chaining:
optimize_prompt()ChatPrompt.toolsOptimizationResult objectsOpik Optimizer is a component of the Opik platform, an open-source LLM evaluation platform by Comet. For more information about the broader Opik ecosystem, visit our Website or Documentation.
Explore Opik Optimizer's capabilities with our interactive notebook:
To get started with Opik Optimizer, follow these steps:
Install the package:
# using pip
pip install opik-optimizer
# using uv (faster)
uv pip install opik-optimizer
Configure Opik (Optional, for advanced features):
If you plan to log optimization experiments to Comet or use Opik Datasets, you'll need to configure the Opik client:
# Install the main Opik CLI (if not already installed)
pip install opik
# Configure your Comet API key and workspace
opik configure
# When prompted, enter your Opik API key and workspace details.
Using Opik with Comet allows you to track your optimization runs, compare results, and manage datasets seamlessly.
Set up LLM Provider API Keys:
Ensure your environment variables are set for the LLM(s) you intend to use. For example, for OpenAI models:
export OPENAI_API_KEY="your_openai_api_key"
The optimizer utilizes LiteLLM, so you can configure keys for various providers as per LiteLLM's documentation.
You'll typically need:
All optimizers follow the same interface, making it easy to switch between algorithms or chain them together:
# All optimizers have the same signature
def optimize_prompt(
self,
prompt: ChatPrompt,
dataset: Dataset,
metric: Callable,
experiment_config: dict | None = None,
n_samples: int | None = None,
auto_continue: bool = False,
agent_class: type[OptimizableAgent] | None = None,
**kwargs: Any,
) -> OptimizationResult
# All optimizers return the same result type
result = optimizer.optimize_prompt(
prompt=prompt,
dataset=dataset,
metric=metric,
n_samples=100
)
# Results can be chained
chained_result = another_optimizer.optimize_prompt(
prompt=ChatPrompt.from_result(result), # Use previous result
dataset=dataset,
metric=metric
)
Here's a brief example of how to use the FewShotBayesianOptimizer. We'll use a sample dataset provided by Opik.
Available sample datasets for testing include "tiny-test", "halu-eval-300", and the
full HotpotQA splits via hotpot(split="train", count=300).
from opik.evaluation.metrics import LevenshteinRatio
from opik_optimizer import FewShotBayesianOptimizer, ChatPrompt
from opik_optimizer.datasets import hotpot
# Load a sample dataset
hot_pot_dataset = hotpot(count=300)
project_name = "optimize-few-shot-bayesian-hotpot" # For Comet logging
# Define the instruction for your chat prompt.
# Input parameters from dataset examples will be interpolated into the full prompt.
prompt = ChatPrompt(
messages=[
{"role": "system", "content": "You are a helpful assistant."},
{"role": "user", "content": "{question}"}
]
)
optimizer = FewShotBayesianOptimizer(
model="gpt-4o-mini", # LiteLLM name to use for generation and optimization
min_examples=3, # Min few-shot examples
max_examples=8, # Max few-shot examples
n_threads=16, # Parallel threads for evaluation
project_name=project_name,
seed=42,
)
def levenshtein_ratio(dataset_item, llm_output):
return LevenshteinRatio().score(reference=dataset_item["answer"], output=llm_output)
# Run the optimization
result = optimizer.optimize_prompt(
prompt=prompt,
dataset=hot_pot_dataset,
metric=levenshtein_ratio,
n_samples=150 # Number of dataset samples for evaluation per trial
)
# Display the best prompt and its score
result.display()
The result object contains the optimized prompt, evaluation scores, and other details from the optimization process. If project_name is provided on the optimizer and Opik is configured, results will also be logged to your Comet workspace.
The optimizer automatically logs run metadata—including optimizer version, tool schemas, prompt messages, and the models used—so you get consistent experiment context without any additional arguments. If you still need custom tags (for example identifying the dataset or task), pass an experiment_config dictionary and your fields will be merged on top of the defaults.
Opik separates prompt optimization, tool use, and tool optimization so you can target exactly what changes.
Tool optimization is currently supported by all optimizers except FewShotBayesianOptimizer, ParameterOptimizer and GEPAOptimizer.
optimize_prompts) controls which prompt roles may be edited.
You can restrict edits to "user" (or any role) while keeping system/assistant messages fixed.model_kwargs={"allow_tool_use": False}.optimize_tools) updates tool descriptions and parameter descriptions only.
Schemas, tool names, and tool lists are unchanged. Set optimize_tools=True to optimize all tools or pass
a dict of {tool_name: bool} to choose specific tools.This separation is intentional: you can keep MCP client templates (system/assistant messages)
fixed while still improving the tool signatures embedded in ChatPrompt.tools.
To avoid overly large tool optimization tasks, optimize_tools=True is limited by
DEFAULT_TOOL_CALL_MAX_TOOLS_TO_OPTIMIZE (default: 3). Use a tool-selection dict to keep it under the limit.
For verbose tool-calling logs (tool names + arguments), set OPIK_OPTIMIZER_LOG_LEVEL=DEBUG.
You can inspect optimizer capabilities at runtime:
optimizer = MetaPromptOptimizer(model="gpt-5")
print(optimizer.supports_prompt_optimization)
print(optimizer.supports_tool_optimization)
print(optimizer.supports_multimodal)
Many optimizers can optimize agents that use function calling, but this is different from true tool optimization. Here's an example with GEPA:
from opik_optimizer import GepaOptimizer, ChatPrompt
from opik_optimizer.utils.tools.wikipedia import search_wikipedia
# GEPA example: optimizing an agent with function calling
prompt = ChatPrompt(
system="You are a helpful assistant. Use the search_wikipedia tool when needed.",
user="{question}",
tools=[
{
"type": "function",
"function": {
"name": "search_wikipedia",
"description": "This function searches Wikipedia abstracts.",
"parameters": {
"type": "object",
"properties": {
"query": {"type": "string", "description": "Search query"}
},
"required": ["query"]
}
}
}
],
function_map={
"search_wikipedia": lambda query: search_wikipedia(query)
}
)
# GEPA optimizes the agent's prompt, not the tools themselves
optimizer = GepaOptimizer(model="gpt-4o-mini")
result = optimizer.optimize_prompt(prompt=prompt, dataset=dataset, metric=metric)
If you need to optimize only parts of a prompt (for example, a specific assistant message
injected by an MCP client), you can use utils.prompt_segments to identify and update specific
segments by ID. This is useful when you want finer control than role-based optimization.
from opik_optimizer import ChatPrompt
from opik_optimizer.utils import prompt_segments
prompt = ChatPrompt(
system="You are a reliable assistant.",
messages=[
{"role": "assistant", "content": "MCP instructions here."},
{"role": "user", "content": "{user_query}"},
],
)
# Inspect segments (system, message:0, message:1, tools...)
segments = prompt_segments.extract_prompt_segments(prompt)
for segment in segments:
print(segment.segment_id, segment.role, segment.content)
# Update only the user message (message:1). apply_segment_updates returns a new
# ChatPrompt and does not mutate the original prompt.
updates = {"message:1": "User question: {user_query}"}
updated_prompt = prompt_segments.apply_segment_updates(prompt, updates)
Note: The segment IDs are stable (e.g., system, user, message:0, tool:<name>).
Use these IDs to target exactly the part you want to optimize.
from opik_optimizer import ChatPrompt, MetaPromptOptimizer
# See scripts/litellm_metaprompt_context7_mcp_example.py or
# scripts/litellm_metaprompt_context7_remote_example.py for working examples.
optimizer = MetaPromptOptimizer(model="gpt-5")
# MCP tools can be configured as OpenAI-style tool entries (local or remote)
prompt = ChatPrompt(
system="Use the docs tool when needed.",
user="{user_query}",
tools=[
{
"type": "mcp",
"server_label": "context7",
"server_url": "https://mcp.context7.com/mcp",
"headers": {"CONTEXT7_API_KEY": "$CONTEXT7_API_KEY"},
"allowed_tools": ["resolve-library-id", "query-docs"],
}
],
)
result = optimizer.optimize_prompt(
prompt=prompt,
dataset=dataset,
metric=metric,
optimize_tools=True, # optimize tool descriptions + parameter descriptions
)
For comprehensive documentation on tool optimization, see the Tool Optimization Guide.
prompt = ChatPrompt(
system="Use tools when needed.",
user="{question}",
tools=[
{
"type": "function",
"function": {
"name": "search_wikipedia",
"description": "Search Wikipedia abstracts.",
"parameters": {
"type": "object",
"properties": {
"query": {"type": "string", "description": "Search query"}
},
"required": ["query"],
},
},
}
],
)
tools = [
{
"type": "mcp",
"server_label": "context7",
"server_url": "https://mcp.context7.com/mcp",
"headers": {"CONTEXT7_API_KEY": "$CONTEXT7_API_KEY"},
"allowed_tools": ["resolve-library-id", "query-docs"],
}
]
cursor_config = {
"mcpServers": {
"context7": {
"url": "https://mcp.context7.com/mcp",
"headers": {"CONTEXT7_API_KEY": "$CONTEXT7_API_KEY"},
}
}
}
# ChatPrompt accepts Cursor style MCP config directly in `tools`.
prompt = ChatPrompt(system="Use MCP tools", user="{user_query}", tools=cursor_config)
The following parameters are deprecated and will be removed in future versions:
num_threads in optimizer constructors: Use n_threads instead# ❌ Deprecated
optimizer = FewShotBayesianOptimizer(
model="gpt-4o-mini",
num_threads=16, # Deprecated
)
# ✅ Correct
optimizer = FewShotBayesianOptimizer(
model="gpt-4o-mini",
n_threads=16, # Use n_threads instead
)
To suppress deprecation warnings during development:
import warnings
warnings.filterwarnings("ignore", category=DeprecationWarning)
The optimizer includes utilities for MCP tool integration:
# Install MCP Python SDK
pip install mcp
# Run MCP examples
python scripts/litellm_metaprompt_context7_mcp_example.py
python scripts/litellm_metaprompt_context7_remote_example.py
Underlying utilities are available in src/opik_optimizer/{utils/toolcalling,utils/prompt_segments}.py.
Local vs remote MCP configuration examples:
local_tool = {
"type": "mcp",
"server_label": "local_docs",
"command": "npx",
"args": ["-y", "@upstash/context7-mcp"],
"env": {},
"allowed_tools": ["get-library-docs"],
}
remote_tool = {
"type": "mcp",
"server_label": "remote_docs",
"server_url": "https://mcp.example.com",
"headers": {"Authorization": "Bearer $TOKEN"},
"allowed_tools": ["search-docs"],
}
cursor_config = {
"mcpServers": {
"context7": {
"url": "https://mcp.context7.com/mcp",
"headers": {"CONTEXT7_API_KEY": "YOUR_API_KEY"},
}
}
}
# Cursor config can be passed directly as ChatPrompt.tools
prompt = ChatPrompt(system="Use MCP tools", user="{user_query}", tools=cursor_config)
**Important:** Tool optimization (MCP) optimizes tool descriptions/signatures. This is different from agent optimization, which optimizes prompt text while tools are used at runtime.
To contribute or use the Opik Optimizer from source:
Clone the Opik repository:
git clone git@github.com:comet-ml/opik.git
Navigate to the optimizer's directory:
cd opik/sdks/opik_optimizer # Adjust 'opik' if you cloned into a different folder name
Install in editable mode (with development dependencies):
pip install -e .[dev]
The [dev] extra installs dependencies useful for development, such as pytest.
>=3.10,<3.13 (see Python version requirements)opik configure)FAQs
Open-source automatic agent and prompt optimization toolkit with Opik
We found that opik-optimizer demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 4 open source maintainers collaborating on the project.
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