Dspy — DSPy: declarative LM programs, auto-optimize prompts, RAG

Dspy

DSPy: declarative LM programs, auto-optimize prompts, RAG.

Skill metadata

Source	Bundled (installed by default)
Path	skills/mlops/research/dspy
Version	1.0.0
Author	Orchestra Research
License	MIT
Dependencies	dspy, openai, anthropic
Tags	Prompt Engineering, DSPy, Declarative Programming, RAG, Agents, Prompt Optimization, LM Programming, Stanford NLP, Automatic Optimization, Modular AI

Reference: full SKILL.md

The following is the complete skill definition that Hermes loads when this skill is triggered. This is what the agent sees as instructions when the skill is active.

DSPy: Declarative Language Model Programming

When to Use This Skill

Use DSPy when you need to:

• Build complex AI systems with multiple components and workflows
• Program LMs declaratively instead of manual prompt engineering
• Optimize prompts automatically using data-driven methods
• Create modular AI pipelines that are maintainable and portable
• Improve model outputs systematically with optimizers
• Build RAG systems, agents, or classifiers with better reliability

GitHub Stars: 22,000+ | Created By: Stanford NLP

Installation

# Stable release
pip install dspy

# Latest development version
pip install git+https://github.com/stanfordnlp/dspy.git

# With specific LM providers
pip install dspy[openai]        # OpenAI
pip install dspy[anthropic]     # Anthropic Claude
pip install dspy[all]           # All providers

Quick Start

Basic Example: Question Answering

import dspy

# Configure your language model
lm = dspy.Claude(model="claude-sonnet-4-5-20250929")
dspy.settings.configure(lm=lm)

# Define a signature (input → output)
class QA(dspy.Signature):
    """Answer questions with short factual answers."""
    question = dspy.InputField()
    answer = dspy.OutputField(desc="often between 1 and 5 words")

# Create a module
qa = dspy.Predict(QA)

# Use it
response = qa(question="What is the capital of France?")
print(response.answer)  # "Paris"

Chain of Thought Reasoning

import dspy

lm = dspy.Claude(model="claude-sonnet-4-5-20250929")
dspy.settings.configure(lm=lm)

# Use ChainOfThought for better reasoning
class MathProblem(dspy.Signature):
    """Solve math word problems."""
    problem = dspy.InputField()
    answer = dspy.OutputField(desc="numerical answer")

# ChainOfThought generates reasoning steps automatically
cot = dspy.ChainOfThought(MathProblem)

response = cot(problem="If John has 5 apples and gives 2 to Mary, how many does he have?")
print(response.rationale)  # Shows reasoning steps
print(response.answer)     # "3"

Core Concepts

1. Signatures

Signatures define the structure of your AI task (inputs → outputs):

# Inline signature (simple)
qa = dspy.Predict("question -> answer")

# Class signature (detailed)
class Summarize(dspy.Signature):
    """Summarize text into key points."""
    text = dspy.InputField()
    summary = dspy.OutputField(desc="bullet points, 3-5 items")

summarizer = dspy.ChainOfThought(Summarize)

When to use each:

• Inline: Quick prototyping, simple tasks
• Class: Complex tasks, type hints, better documentation

2. Modules

Modules are reusable components that transform inputs to outputs:

dspy.Predict

Basic prediction module:

predictor = dspy.Predict("context, question -> answer")
result = predictor(context="Paris is the capital of France",
                   question="What is the capital?")

dspy.ChainOfThought

Generates reasoning steps before answering:

cot = dspy.ChainOfThought("question -> answer")
result = cot(question="Why is the sky blue?")
print(result.rationale)  # Reasoning steps
print(result.answer)     # Final answer

dspy.ReAct

Agent-like reasoning with tools:

from dspy.predict import ReAct

class SearchQA(dspy.Signature):
    """Answer questions using search."""
    question = dspy.InputField()
    answer = dspy.OutputField()

def search_tool(query: str) -> str:
    """Search Wikipedia."""
    # Your search implementation
    return results

react = ReAct(SearchQA, tools=[search_tool])
result = react(question="When was Python created?")

dspy.ProgramOfThought

Generates and executes code for reasoning:

pot = dspy.ProgramOfThought("question -> answer")
result = pot(question="What is 15% of 240?")
# Generates: answer = 240 * 0.15

3. Optimizers

Optimizers improve your modules automatically using training data:

BootstrapFewShot

Learns from examples:

from dspy.teleprompt import BootstrapFewShot

# Training data
trainset = [
    dspy.Example(question="What is 2+2?", answer="4").with_inputs("question"),
    dspy.Example(question="What is 3+5?", answer="8").with_inputs("question"),
]

# Define metric
def validate_answer(example, pred, trace=None):
    return example.answer == pred.answer

# Optimize
optimizer = BootstrapFewShot(metric=validate_answer, max_bootstrapped_demos=3)
optimized_qa = optimizer.compile(qa, trainset=trainset)

# Now optimized_qa performs better!

MIPRO (Most Important Prompt Optimization)

Iteratively improves prompts:

from dspy.teleprompt import MIPRO

optimizer = MIPRO(
    metric=validate_answer,
    num_candidates=10,
    init_temperature=1.0
)

optimized_cot = optimizer.compile(
    cot,
    trainset=trainset,
    num_trials=100
)

BootstrapFinetune

Creates datasets for model fine-tuning:

from dspy.teleprompt import BootstrapFinetune

optimizer = BootstrapFinetune(metric=validate_answer)
optimized_module = optimizer.compile(qa, trainset=trainset)

# Exports training data for fine-tuning

4. Building Complex Systems

Multi-Stage Pipeline

import dspy

class MultiHopQA(dspy.Module):
    def __init__(self):
        super().__init__()
        self.retrieve = dspy.Retrieve(k=3)
        self.generate_query = dspy.ChainOfThought("question -> search_query")
        self.generate_answer = dspy.ChainOfThought("context, question -> answer")

    def forward(self, question):
        # Stage 1: Generate search query
        search_query = self.generate_query(question=question).search_query

        # Stage 2: Retrieve context
        passages = self.retrieve(search_query).passages
        context = "\n".join(passages)

        # Stage 3: Generate answer
        answer = self.generate_answer(context=context, question=question).answer
        return dspy.Prediction(answer=answer, context=context)

# Use the pipeline
qa_system = MultiHopQA()
result = qa_system(question="Who wrote the book that inspired the movie Blade Runner?")

RAG System with Optimization

import dspy
from dspy.retrieve.chromadb_rm import ChromadbRM

# Configure retriever
retriever = ChromadbRM(
    collection_name="documents",
    persist_directory="./chroma_db"
)

class RAG(dspy.Module):
    def __init__(self, num_passages=3):
        super().__init__()
        self.retrieve = dspy.Retrieve(k=num_passages)
        self.generate = dspy.ChainOfThought("context, question -> answer")

    def forward(self, question):
        context = self.retrieve(question).passages
        return self.generate(context=context, question=question)

# Create and optimize
rag = RAG()

# Optimize with training data
from dspy.teleprompt import BootstrapFewShot

optimizer = BootstrapFewShot(metric=validate_answer)
optimized_rag = optimizer.compile(rag, trainset=trainset)

LM Provider Configuration

Anthropic Claude

import dspy

lm = dspy.Claude(
    model="claude-sonnet-4-5-20250929",
    api_key="your-api-key",  # Or set ANTHROPIC_API_KEY env var
    max_tokens=1000,
    temperature=0.7
)
dspy.settings.configure(lm=lm)

OpenAI

lm = dspy.OpenAI(
    model="gpt-4",
    api_key="your-api-key",
    max_tokens=1000
)
dspy.settings.configure(lm=lm)

Local Models (Ollama)

lm = dspy.OllamaLocal(
    model="llama3.1",
    base_url="http://localhost:11434"
)
dspy.settings.configure(lm=lm)

Multiple Models

# Different models for different tasks
cheap_lm = dspy.OpenAI(model="gpt-3.5-turbo")
strong_lm = dspy.Claude(model="claude-sonnet-4-5-20250929")

# Use cheap model for retrieval, strong model for reasoning
with dspy.settings.context(lm=cheap_lm):
    context = retriever(question)

with dspy.settings.context(lm=strong_lm):
    answer = generator(context=context, question=question)

Common Patterns

Pattern 1: Structured Output

from pydantic import BaseModel, Field

class PersonInfo(BaseModel):
    name: str = Field(description="Full name")
    age: int = Field(description="Age in years")
    occupation: str = Field(description="Current job")

class ExtractPerson(dspy.Signature):
    """Extract person information from text."""
    text = dspy.InputField()
    person: PersonInfo = dspy.OutputField()

extractor = dspy.TypedPredictor(ExtractPerson)
result = extractor(text="John Doe is a 35-year-old software engineer.")
print(result.person.name)  # "John Doe"
print(result.person.age)   # 35

Pattern 2: Assertion-Driven Optimization

import dspy
from dspy.primitives.assertions import assert_transform_module, backtrack_handler

class MathQA(dspy.Module):
    def __init__(self):
        super().__init__()
        self.solve = dspy.ChainOfThought("problem -> solution: float")

    def forward(self, problem):
        solution = self.solve(problem=problem).solution

        # Assert solution is numeric
        dspy.Assert(
            isinstance(float(solution), float),
            "Solution must be a number",
            backtrack=backtrack_handler
        )

        return dspy.Prediction(solution=solution)

Pattern 3: Self-Consistency

import dspy
from collections import Counter

class ConsistentQA(dspy.Module):
    def __init__(self, num_samples=5):
        super().__init__()
        self.qa = dspy.ChainOfThought("question -> answer")
        self.num_samples = num_samples

    def forward(self, question):
        # Generate multiple answers
        answers = []
        for _ in range(self.num_samples):
            result = self.qa(question=question)
            answers.append(result.answer)

        # Return most common answer
        most_common = Counter(answers).most_common(1)[0][0]
        return dspy.Prediction(answer=most_common)

Pattern 4: Retrieval with Reranking

class RerankedRAG(dspy.Module):
    def __init__(self):
        super().__init__()
        self.retrieve = dspy.Retrieve(k=10)
        self.rerank = dspy.Predict("question, passage -> relevance_score: float")
        self.answer = dspy.ChainOfThought("context, question -> answer")

    def forward(self, question):
        # Retrieve candidates
        passages = self.retrieve(question).passages

        # Rerank passages
        scored = []
        for passage in passages:
            score = float(self.rerank(question=question, passage=passage).relevance_score)
            scored.append((score, passage))

        # Take top 3
        top_passages = [p for _, p in sorted(scored, reverse=True)[:3]]
        context = "\n\n".join(top_passages)

        # Generate answer
        return self.answer(context=context, question=question)

Evaluation and Metrics

Custom Metrics

def exact_match(example, pred, trace=None):
    """Exact match metric."""
    return example.answer.lower() == pred.answer.lower()

def f1_score(example, pred, trace=None):
    """F1 score for text overlap."""
    pred_tokens = set(pred.answer.lower().split())
    gold_tokens = set(example.answer.lower().split())

    if not pred_tokens:
        return 0.0

    precision = len(pred_tokens & gold_tokens) / len(pred_tokens)
    recall = len(pred_tokens & gold_tokens) / len(gold_tokens)

    if precision + recall == 0:
        return 0.0

    return 2 * (precision * recall) / (precision + recall)

Evaluation

from dspy.evaluate import Evaluate

# Create evaluator
evaluator = Evaluate(
    devset=testset,
    metric=exact_match,
    num_threads=4,
    display_progress=True
)

# Evaluate model
score = evaluator(qa_system)
print(f"Accuracy: {score}")

# Compare optimized vs unoptimized
score_before = evaluator(qa)
score_after = evaluator(optimized_qa)
print(f"Improvement: {score_after - score_before:.2%}")

Best Practices

1. Start Simple, Iterate

# Start with Predict
qa = dspy.Predict("question -> answer")

# Add reasoning if needed
qa = dspy.ChainOfThought("question -> answer")

# Add optimization when you have data
optimized_qa = optimizer.compile(qa, trainset=data)

2. Use Descriptive Signatures

# ❌ Bad: Vague
class Task(dspy.Signature):
    input = dspy.InputField()
    output = dspy.OutputField()

# ✅ Good: Descriptive
class SummarizeArticle(dspy.Signature):
    """Summarize news articles into 3-5 key points."""
    article = dspy.InputField(desc="full article text")
    summary = dspy.OutputField(desc="bullet points, 3-5 items")

3. Optimize with Representative Data

# Create diverse training examples
trainset = [
    dspy.Example(question="factual", answer="...).with_inputs("question"),
    dspy.Example(question="reasoning", answer="...").with_inputs("question"),
    dspy.Example(question="calculation", answer="...").with_inputs("question"),
]

# Use validation set for metric
def metric(example, pred, trace=None):
    return example.answer in pred.answer

4. Save and Load Optimized Models

# Save
optimized_qa.save("models/qa_v1.json")

# Load
loaded_qa = dspy.ChainOfThought("question -> answer")
loaded_qa.load("models/qa_v1.json")

5. Monitor and Debug

# Enable tracing
dspy.settings.configure(lm=lm, trace=[])

# Run prediction
result = qa(question="...")

# Inspect trace
for call in dspy.settings.trace:
    print(f"Prompt: {call['prompt']}")
    print(f"Response: {call['response']}")

Comparison to Other Approaches

Feature	Manual Prompting	LangChain	DSPy
Prompt Engineering	Manual	Manual	Automatic
Optimization	Trial & error	None	Data-driven
Modularity	Low	Medium	High
Type Safety	No	Limited	Yes (Signatures)
Portability	Low	Medium	High
Learning Curve	Low	Medium	Medium-High

When to choose DSPy:

• You have training data or can generate it
• You need systematic prompt improvement
• You’re building complex multi-stage systems
• You want to optimize across different LMs

When to choose alternatives:

• Quick prototypes (manual prompting)
• Simple chains with existing tools (LangChain)
• Custom optimization logic needed

Resources

• Documentation: https://dspy.ai
• GitHub: https://github.com/stanfordnlp/dspy (22k+ stars)
• Discord: https://discord.gg/XCGy2WDCQB
• Twitter: @DSPyOSS
• Paper: “DSPy: Compiling Declarative Language Model Calls into Self-Improving Pipelines”

See Also

• references/modules.md - Detailed module guide (Predict, ChainOfThought, ReAct, ProgramOfThought)
• references/optimizers.md - Optimization algorithms (BootstrapFewShot, MIPRO, BootstrapFinetune)
• references/examples.md - Real-world examples (RAG, agents, classifiers)