Presets

Named constructors for common agent configurations.

The pkg/preset package provides ready-made agent constructors for the most common patterns. They set sensible defaults and reduce boilerplate — without removing any flexibility.

import "github.com/lioarce01/chainforge/pkg/preset"

Chatbot

A conversational agent with memory and a 1-iteration loop (no tool calling).

agent, err := preset.Chatbot(provider, "claude-sonnet-4-6", preset.ChatbotConfig{
    SystemPrompt: "You are a helpful assistant.",
    MaxHistory:   20,
})

result, err := agent.Run(ctx, "session-1", "Hello!")

Defaults set by Chatbot:

• WithMemory(inmemory.New()) — in-memory store created automatically (override via Memory field)
• WithMaxIterations(1) — single-turn response, no agentic loop

Override any default using the extra options variadic:

agent, err := preset.Chatbot(provider, "claude-sonnet-4-6",
    preset.ChatbotConfig{SystemPrompt: "You are a helpful assistant."},
    chainforge.WithRetry(3),
    chainforge.WithRunTimeout(30*time.Second),
)

ToolAgent

An agent with tools, automatic retry, and a multi-iteration loop.

agent, err := preset.ToolAgent(provider, "claude-sonnet-4-6", preset.ToolAgentConfig{
    SystemPrompt:  "You are a research assistant with access to the web.",
    Tools:         []core.Tool{searchTool, calcTool},
    MaxIterations: 10,
    MaxRetries:    3,
})

result, err := agent.Run(ctx, "session-1", "What is the population of Tokyo?")

Defaults set by ToolAgent:

• WithMaxIterations(10) when MaxIterations is 0
• WithRetry(3) when MaxRetries is 0

With persistent memory:

store, _ := sqlite.New("./chat.db")

agent, err := preset.ToolAgent(provider, "claude-sonnet-4-6", preset.ToolAgentConfig{
    SystemPrompt: "You are a research assistant.",
    Tools:        []core.Tool{searchTool},
    Memory:       store,
})

When to use presets vs. raw NewAgent

Scenario	Recommendation
Quick chatbot or demo	preset.Chatbot
Agent with tools	preset.ToolAgent
Fine-grained control (custom retry ordering, MCP, OTel)	chainforge.NewAgent directly
Multiple agents in a pipeline	Build each with NewAgent; presets are for standalone agents

Presets call chainforge.NewAgent internally — there is no runtime overhead. Extra options passed as the variadic override any preset-supplied option.