cruise-llm 0.2.0

The fastest way to build, chain, and reuse LLM agents and flows

🏎️ cruise-llm

Quickly build and reuse LLM workflows/agents with a clean, composable API — inspired by scikit-learn's chainability and litellm's model flexibility.

from cruise_llm import LLM
LLM().user("Explain quantum computing").chat(stream=True)

---

⛓️ Multi-turn Prompt Queues

Build complex micro-workflows by queuing prompts that the model will execute sequentially.

# Automatic multi-step processing
news_processor = (
    LLM(model="fast")
    .user(f"Process this article: {raw_text}")
    .queue("Summarize the key points into 3 bullet points for an executive.")
    .queue("Translate those points into Spanish.")
    .queue("Format the Spanish summary as a Slack message with emojis.")
    .chat()
)

# Create reusable bot templates
def style_refiner(style):
    return LLM().sys(f"Rewrite in a {style} tone").queue("Make it half the length")

casual = style_refiner("casual")
formal = style_refiner("formal")

casual.user("We need to discuss Q3 deliverables").res()
formal.user("hey wanna grab coffee and chat about the project?").res()

---

🔧 Easy Tool Calling for Fast Agent Building

Simply define functions, no schema necessary:

def search_docs(query: str):
    """Search internal documentation."""
    return f"Found: '{query}' appears in onboarding.md and api-reference.md"

def create_ticket(title: str, priority: str):
    """Create a support ticket."""
    return f"Created ticket #{hash(title) % 1000}: {title} [{priority}]"

def send_slack(channel: str, message: str):
    """Send a Slack message."""
    return f"Sent to #{channel}: {message[:50]}..."

support_agent = (
    LLM()
    .sys("You are a support agent")
    .tools(fns=[search_docs, create_ticket, send_slack])
)

support_agent.user("User can't log in. Check docs, create a P1 ticket, and alert #incidents").chat()

---

🔄 Flexible conversations

Chat instances with swappable models and minimal verbosity:

chat1 = (
    LLM(model="fast")
    .sys("You are a bitcoin analyst")
    .user("What is proof of work?").chat()
    .user("Steel man the case for bitcoin mining").chat()
    .user("Now steel man the case against").chat()
)

# Replay history with more intelligent yet expensive config
chat2 = chat1.run_history(model="best", reasoning=True, reasoning_effort="high")

# Save chat histories to analyze offline or load later
chat1.save_llm("chats/bitcoin_analysis_fast_model.json")
chat2.save_llm("chats/bitcoin_analysis_best_model.json")

---

🔀 Model Discovery & A/B Testing

Pick specific models or by category:

LLM(model="gpt-5-2")
LLM(model="best")   # top-tier reasoning
LLM(model="fast")  
LLM(model="cheap")  
LLM(model="open")   # open-source models

# Discover and filter what's available
LLM().get_models("claude")

# A/B test across providers
prompt = "Write a haiku about debugging"
for model in ["gpt-5-2", "qwen/qwen3-32b", "claude-opus-4-5", "gemini-3-pro"]:
    LLM(model=model).user(prompt).response()

---

💾 Save, Load, Export

# Save an agent config
researcher = LLM("claude-sonnet-4-5").tools(search=True)
researcher.save_llm("agents/researcher.json")

# Load
r = LLM.load_llm("agents/researcher.json")
r.user(f"What happened in tech {todays_date}?").chat()

# Export conversation to markdown
r.to_md(f"tech_briefing/{todays_date}.md")

---

📦 Install

pip install cruise-llm

Your access to models is based on your API keys from the various providers—keys are available for free from most providers. Create a local .env file in your project root with at least one API key. Use litellm-specific variable names:

OPENAI_API_KEY=sk-proj-...
ANTHROPIC_API_KEY=sk-ant-...
GEMINI_API_KEY=AIza...
GROQ_API_KEY=gsk_...
XAI_API_KEY=xai-...