AgentLang

A tiny, self-contained DSL for agentic workflows.

Define agents, typed tasks, declarative workflows, and explicit pipelines — then run them with deterministic mock adapters or live LLM backends (OpenAI or Anthropic/Claude). No framework. No magic. Everything compiles from source to execution in Python.

tool web_search(query: String) -> List[Obj{title: String, url: String, snippet: String}] {}

agent planner {
  model: "gpt-4.1"
  , tools: [web_search]
}

agent reviewer {
  model: "gpt-4.1-mini"
  , tools: [web_search]
}

task plan_blog(topic: String) -> Obj{outline: String, sources: List[String]} by agent {}
task review_outline(topic: String, outline: String, sources: List[String]) -> Obj{approved: Bool, feedback: String} by agent {}
task revise_outline(topic: String, outline: String, sources: List[String], feedback: String) -> Obj{outline: String, sources: List[String]} by agent {}

workflow publish_topic_blog(topic: String) -> String {
  stage plan = planner does plan_blog(topic);
  review outline = reviewer checks plan revise with planner using revise_outline max_rounds 2;
  return outline.outline;
}

$ python main.py examples/blog.agent blog_post \
    --input '{"topic":"agent memory patterns"}'
{
  "result": "[writer] Draft article:\n[planner] key points for 'agent memory patterns'"
}

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Why AgentLang?

Most "agent frameworks" hide the execution model behind layers of abstraction. AgentLang does the opposite — the language has a formal grammar, a static type checker, and a runtime you can read in an afternoon.

	AgentLang
External dependencies	None (core)
Type checking	Static, structural
High-level authoring	workflow, stage, review
Parallel execution	Built-in parallel { } join
Looping	while, break, continue
Retry / fallback	First-class syntax
LLM backend	Optional (--adapter live or --adapter anthropic)

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Where to start

• New to AgentLang?

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  Follow the tutorial to run your first pipeline or workflow in under five minutes.

  Quick Start

• Learn the language

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  Understand agents, tasks, workflows, pipelines, the type system, and parallel execution.

  Concepts

• Connect to OpenAI or Anthropic

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  Switch from deterministic mock mode to live LLM adapters.

  Adapters

• Read the full reference

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  Complete syntax, CLI flags, and runtime semantics.

  Language Reference