// ResearchAgent: generate a research plan
func NewResearchAgent(model model.ToolCallingChatModel) adk.Agent {
    agent, _ := adk.NewChatModelAgent(context.Background(), &adk.ChatModelAgentConfig{
       Name:        "ResearchAgent",
       Description: "Generates a detailed research plan for a given topic.",
       Instruction: `
You are a research planner. Given a topic, output a step-by-step research plan with key stages and milestones.
Output ONLY the plan, no extra text.`,
       Model: model,
    })
    return agent
}

// WriterAgent: write a report based on the plan
func NewWriterAgent(model model.ToolCallingChatModel) adk.Agent {
    agent, _ := adk.NewChatModelAgent(context.Background(), &adk.ChatModelAgentConfig{
       Name:        "WriterAgent",
       Description: "Writes a report based on a research plan.",
       Instruction: `
You are an academic writer. Given a research plan, expand it into a structured report with details and analysis.
Output ONLY the report, no extra text.`,
       Model: model,
    })
    return agent
}

// ReportSupervisor: coordinate research and writing
func NewReportSupervisor(model model.ToolCallingChatModel) adk.Agent {
    agent, _ := adk.NewChatModelAgent(context.Background(), &adk.ChatModelAgentConfig{
        Name:        "ReportSupervisor",
        Description: "Coordinates research and writing to generate a report.",
        Instruction: `
You are a project supervisor. Your task is to coordinate two sub-agents:
- ResearchAgent: generates a research plan.
- WriterAgent: writes a report based on the plan.

Workflow:
1. When receiving a topic, first transfer the task to ResearchAgent.
2. After ResearchAgent finishes, transfer the task to WriterAgent with the plan as input.
3. After WriterAgent finishes, output the final report.`,
        Model: model,
    })
    return agent
}

import (
    "context"

    "github.com/cloudwego/eino-ext/components/model/openai"
    "github.com/cloudwego/eino/adk"
    "github.com/cloudwego/eino/adk/prebuilt/supervisor"
    "github.com/cloudwego/eino/components/model"
    "github.com/cloudwego/eino/schema"
)

func main() {
    ctx := context.Background()

    // 1) Create model (e.g., GPT‑4o)
    model, _ := openai.NewChatModel(ctx, &openai.ChatModelConfig{
       APIKey: "YOUR_API_KEY",
       Model:  "gpt-4o",
    })

    // 2) Create subagents and supervisor
    researchAgent := NewResearchAgent(model)
    writerAgent := NewWriterAgent(model)
    reportSupervisor := NewReportSupervisor(model)

    // 3) Compose supervisor and subagents
    supervisorAgent, _ := supervisor.New(ctx, &supervisor.Config{
       Supervisor: reportSupervisor,
       SubAgents:  []adk.Agent{researchAgent, writerAgent},
    })

    // 4) Run Supervisor pattern
    iter := supervisorAgent.Run(ctx, &adk.AgentInput{
       Messages: []adk.Message{
          schema.UserMessage("Write a report on the history of Large Language Models."),
       },
       EnableStreaming: true,
    })

    // 5) Consume event stream (print results)
    for {
       event, ok := iter.Next()
       if !ok {
          break
       }
       if event.Output != nil && event.Output.MessageOutput != nil {
          msg, _ := event.Output.MessageOutput.GetMessage()
          println("Agent[" + event.AgentName + "]:\n" + msg.Content + "\n===========")
       }
    }
}

Agent[ReportSupervisor]:

===========
Agent[ReportSupervisor]:
successfully transferred to agent [ResearchAgent]
===========
Agent[ResearchAgent]:
1. **Scope Definition & Background Research**  
   - Task: Define "Large Language Model" (LLM) for the report (e.g., size thresholds, key characteristics: transformer-based, large-scale pretraining, general-purpose).  
   - Task: Identify foundational NLP/AI concepts pre-LLMs (statistical models, early neural networks, word embeddings) to contextualize origins.  
   - Milestone: 3-day literature review of academic definitions, industry reports, and AI historiographies to finalize scope.  

2. **Chronological Periodization**  
   - Task: Divide LLM history into distinct eras (e.g., Pre-2017: Pre-transformer foundations; 2017-2020: Transformer revolution & early LLMs; 2020-Present: Scaling & mainstream adoption).  
   - Task: Map key events, models, and breakthroughs per era (e.g., 2017: "Attention Is All You Need"; 2018: GPT-1/BERT; 2020: GPT-3; 2022: ChatGPT; 2023: Llama 2).  
   - Milestone: 10-day timeline draft with annotated model releases, research papers, and technological shifts.  

3. **Key Technical Milestones**  
   - Task: Deep-dive into critical innovations (transformer architecture, pretraining-fine-tuning paradigm, scaling laws, in-context learning).  
   - Task: Extract details from seminal papers (authors, institutions, methodologies, performance benchmarks).  
   - Milestone: 1-week analysis of 5-7 foundational papers (e.g., Vaswani et al. 2017; Radford et al. 2018; Devlin et al. 2018) with technical summaries.  

4. **Stakeholder Mapping**  
   - Task: Identify key organizations (OpenAI, Google DeepMind, Meta AI, Microsoft Research) and academic labs (Stanford, Berkeley) driving LLM development.  
   - Task: Document institutional contributions (e.g., OpenAI’s GPT series, Google’s BERT/PaLM, Meta’s Llama) and research priorities (open vs. closed models).  
   - Milestone: 5-day stakeholder profile draft with org-specific timelines and model lineages.  

5. **Technical Evolution & Innovation Trajectory**  
   - Task: Analyze shifts in architecture (from RNNs/LSTMs to transformers), training paradigms (pretraining + fine-tuning → instruction tuning → RLHF), and compute scaling (parameters, data size, GPU usage over time).  
   - Task: Link technical changes to performance improvements (e.g., GPT-1 (124M params) vs. GPT-4 (100B+ params): task generalization, emergent abilities).  
   - Milestone: 1-week technical trajectory report with data visualizations (param scaling, benchmark scores over time).  

6. **Impact & Societal Context**  
   - Task: Research LLM impact on NLP tasks (translation, summarization, QA) and beyond (education, content creation, policy).  
   - Task: Document cultural/industry shifts (rise of prompt engineering, "AI-native" products, public perception post-ChatGPT).  
   - Milestone: 5-day impact analysis integrating case studies (e.g., GitHub Copilot, healthcare LLMs) and media/scholarly discourse.  

7. **Challenges & Critiques (Historical Perspective)**  
   - Task: Track historical limitations (pre-2020: data sparsity, task specificity; post-2020: bias, misinformation, energy use) and responses (e.g., 2019: BERT bias audits; 2023: EU AI Act).  
   - Task: Cite key critiques (e.g., "On the Dangers of Stochastic Parrots," 2021) and industry/academic reactions.  
   - Milestone: 5-day challenge timeline linking issues to their emergence and mitigation efforts.  

8. **Synthesis & Narrative Drafting**  
   - Task: Integrate chronological, technical, and societal data into a coherent narrative (origins → revolution → scaling → mainstream impact).  
   - Task: Outline report structure (Abstract, Introduction, Era-by-Era Analysis, Key Innovations, Stakeholders, Impact, Challenges, Conclusion).  
   - Milestone: 1-week first draft of full report (8,000–10,000 words).  

9. **Validation & Fact-Checking**  
   - Task: Verify model release dates, paper citations, parameter counts, and stakeholder claims via primary sources (original papers, official press releases, archived GitHub repos).  
   - Task: Cross-check with secondary sources (AI history books, expert interviews, peer-reviewed historiographies).  
   - Milestone: 3-day validation report flagging/correcting inaccuracies.  

10. **Finalization & Revision**  
    - Task: Edit for clarity, narrative flow, and consistency; refine visuals (timelines, param scaling charts).  
    - Task: Format references (APA/MLA) and appendices (model comparison table, key paper list).  
    - Milestone: 2-day final report submission.
===========
Agent[ResearchAgent]:

===========
Agent[ResearchAgent]:
successfully transferred to agent [ReportSupervisor]
===========
Agent[ReportSupervisor]:

===========
Agent[ReportSupervisor]:
successfully transferred to agent [WriterAgent]
===========
Agent[WriterAgent]:
# The History of Large Language Models: From Foundations to Mainstream Revolution  


## Abstract  
Large Language Models (LLMs) represent one of the most transformative technological innovations of the 21st century, enabling machines to understand, generate, and manipulate human language with unprecedented fluency. This report traces the historical trajectory of LLMs, from their conceptual roots in early natural language processing (NLP) to their current status as mainstream tools. It examines key technical milestones—including the invention of the transformer architecture, the rise of pretraining-fine-tuning paradigms, and the scaling of model parameters—and contextualizes these within the contributions of academic labs and tech giants. The report also analyzes societal impacts, from revolutionizing NLP tasks to sparking debates over bias, misinformation, and AI regulation. By synthesizing chronological, technical, and cultural data, this history reveals how LLMs evolved from niche research experiments to agents of global change.  


## 1. Introduction: Defining Large Language Models  
A **Large Language Model (LLM)** is a type of machine learning model designed to process and generate human language by learning patterns from massive text datasets. Key characteristics include: (1) a transformer-based architecture, enabling parallel processing of text sequences; (2) large-scale pretraining on diverse corpora (e.g., books, websites, articles); (3) general-purpose functionality, allowing adaptation to tasks like translation, summarization, or dialogue without task-specific engineering; and (4) scale, typically defined by billions (or tens of billions) of parameters (adjustable weights that capture linguistic patterns).  

LLMs emerged from decades of NLP research, building on foundational concepts like statistical models (e.g., n-grams), early neural networks (e.g., recurrent neural networks [RNNs]), and word embeddings (e.g., Word2Vec, GloVe). By the 2010s, these predecessors had laid groundwork for "language understanding," but were limited by task specificity (e.g., a model trained for translation could not summarize text) and data sparsity. LLMs addressed these gaps by prioritizing scale, generality, and architectural innovation—ultimately redefining the boundaries of machine language capability.  


## 2. Era-by-Era Analysis: The Evolution of LLMs  

### 2.1 Pre-2017: Pre-Transformer Foundations (1950s–2016)  
The roots of LLMs lie in mid-20th-century NLP, when researchers first sought to automate language tasks. Early efforts relied on rule-based systems (e.g., 1950s machine translation using syntax rules) and statistical methods (e.g., 1990s n-gram models for speech recognition). By the 2010s, neural networks gained traction: RNNs and long short-term memory (LSTM) models (Hochreiter & Schmidhuber, 1997) enabled sequence modeling, while word embeddings (Mikolov et al., 2013) represented words as dense vectors, capturing semantic relationships.  

Despite progress, pre-2017 models faced critical limitations: RNNs/LSTMs processed text sequentially, making them slow to train and unable to handle long-range dependencies (e.g., linking "it" in a sentence to a noun paragraphs earlier). Data was also constrained: models like Word2Vec trained on millions, not billions, of tokens. These bottlenecks set the stage for a paradigm shift.  


### 2.2 2017–2020: The Transformer Revolution and Early LLMs  
The year 2017 marked the dawn of the LLM era with the publication of *"Attention Is All You Need"* (Vaswani et al.), which introduced the **transformer architecture**. Unlike RNNs, transformers use "self-attention" mechanisms to weigh the importance of different words in a sequence simultaneously, enabling parallel computation and capturing long-range dependencies. This breakthrough reduced training time and improved performance on language tasks.  

#### Key Models and Breakthroughs:  
- **2018**: OpenAI released **GPT-1** (Radford et al.), the first transformer-based LLM. With 124 million parameters, it introduced the "pretraining-fine-tuning" paradigm: pretraining on a large unlabeled corpus (BooksCorpus) to learn general language patterns, then fine-tuning on task-specific labeled data (e.g., sentiment analysis).  
- **2018**: Google published **BERT** (Devlin et al.), a bidirectional transformer that processed text from left-to-right *and* right-to-left, outperforming GPT-1 on context-dependent tasks like question answering. BERT’s success popularized "contextual embeddings," where word meaning depends on surrounding text (e.g., "bank" as a financial institution vs. a riverbank).  
- **2019**: OpenAI scaled up with **GPT-2** (1.5 billion parameters), demonstrating improved text generation but sparking early concerns about misuse (OpenAI initially delayed full release over fears of disinformation).  
- **2020**: Google’s **T5** (Text-to-Text Transfer Transformer) unified NLP tasks under a single "text-to-text" framework, simplifying model adaptation.  


### 2.3 2020–Present: Scaling, Emergence, and Mainstream Adoption  
The 2020s saw LLMs transition from research curiosities to global phenomena, driven by exponential scaling of parameters, data, and compute.  

#### Key Developments:  
- **2020**: OpenAI’s **GPT-3** (175 billion parameters) marked a turning point. Trained on 45 TB of text, it exhibited "few-shot" and "zero-shot" learning. GPT-3’s API release introduced LLMs to developers.  
- **2022**: **ChatGPT** (GPT-3.5) brought LLMs to the public with **RLHF** alignment.  
- **2023**: Meta’s **Llama 2** opened weights for research and commercial use; OpenAI’s **GPT-4** expanded multimodality and reasoning.  
- **2023–2024**: Scaling race continued (PaLM 2, Claude 2, Mistral, Falcon); compute usage skyrocketed.  
===========
Agent[WriterAgent]:

===========
Agent[WriterAgent]:
successfully transferred to agent [ReportSupervisor]
===========

// Wrapper
func AgentWithDeterministicTransferTo(_ context.Context, config *DeterministicTransferConfig) Agent

// Config
type DeterministicTransferConfig struct {
    Agent        Agent    // target agent to enhance
    ToAgentNames []string // destination agent names to transfer to after completion
}

// Wrapper for a regular Agent
type agentWithDeterministicTransferTo struct {
    agent        Agent    // original agent
    toAgentNames []string // destination agent names
}

// Run: execute original agent and append Transfer after completion
func (a *agentWithDeterministicTransferTo) Run(ctx context.Context, input *AgentInput, options ...AgentRunOption) *AsyncIterator[*AgentEvent] {
    aIter := a.agent.Run(ctx, input, options...)
    
    iterator, generator := NewAsyncIteratorPair[*AgentEvent]()
    
    // asynchronously forward original events and append Transfer
    go appendTransferAction(ctx, aIter, generator, a.toAgentNames)
    
    return iterator
}

type resumableAgentWithDeterministicTransferTo struct {
    agent        ResumableAgent // resumable original agent
    toAgentNames []string       // destination agent names
}

// Resume: resume original agent and append Transfer after completion
func (a *resumableAgentWithDeterministicTransferTo) Resume(ctx context.Context, info *ResumeInfo, opts ...AgentRunOption) *AsyncIterator[*AgentEvent] {
    aIter := a.agent.Resume(ctx, info, opts...)
    iterator, generator := NewAsyncIteratorPair[*AgentEvent]()
    go appendTransferAction(ctx, aIter, generator, a.toAgentNames)
    return iterator
}

func appendTransferAction(ctx context.Context, aIter *AsyncIterator[*AgentEvent], generator *AsyncGenerator[*AgentEvent], toAgentNames []string) {
    defer func() {
        // panic handling: capture and send as error event
        if panicErr := recover(); panicErr != nil {
            generator.Send(&AgentEvent{Err: safe.NewPanicErr(panicErr, debug.Stack())})
        }
        generator.Close() // close generator when stream ends
    }()

    interrupted := false

    // 1) forward all original events
    for {
        event, ok := aIter.Next()
        if !ok {
            break
        }
        generator.Send(event)

        // check interrupt (e.g., InterruptAction)
        if event.Action != nil && event.Action.Interrupted != nil {
            interrupted = true
        } else {
            interrupted = false
        }
    }

    // 2) if not interrupted and destinations exist, generate Transfer events
    if !interrupted && len(toAgentNames) > 0 {
        for _, toAgentName := range toAgentNames {
            // generate assistant tip and transfer action messages
            aMsg, tMsg := GenTransferMessages(ctx, toAgentName)
            // send assistant event
            aEvent := EventFromMessage(aMsg, nil, schema.Assistant, "")
            generator.Send(aEvent)
            // send transfer tool event
            tEvent := EventFromMessage(tMsg, nil, schema.Tool, tMsg.ToolName)
            tEvent.Action = &AgentAction{
                TransferToAgent: &TransferToAgentAction{
                    DestAgentName: toAgentName,
                },
            }
            generator.Send(tEvent)
        }
    }
}