Sequential Planning

# Sequential plan executor
class SequentialPlanner:
    def __init__(self, tools: dict):
        self.tools = tools

    def create_plan(self, goal: str) -> list:
        """
        In a real system, a language model creates the plan.
        Here we return a hardcoded example plan.
        """
        return [
            {"step": 1, "action": "web_search",
             "args": {"query": f"{goal} — background research"},
             "description": "Gather background information"},

            {"step": 2, "action": "web_search",
             "args": {"query": f"{goal} — latest news"},
             "description": "Find recent developments"},

            {"step": 3, "action": "summarise",
             "args": {"text": "{{step_1_result}} {{step_2_result}}"},
             "description": "Summarise all research"},

            {"step": 4, "action": "create_report",
             "args": {"summary": "{{step_3_result}}", "title": goal},
             "description": "Format as report"},
        ]

    def execute_plan(self, plan: list) -> dict:
        """Execute each step in order."""
        results = {}

        for step_def in plan:
            step_num = step_def["step"]
            action = step_def["action"]

            # Resolve references to previous step results
            args = {k: results.get(v.replace("{{", "").replace("}}", ""), v)
                    if isinstance(v, str) and v.startswith("{{") else v
                    for k, v in step_def["args"].items()}

            print(f"  Step {step_num}: {step_def['description']}")

            if action in self.tools:
                result = self.tools[action](**args)
                results[f"step_{step_num}_result"] = result
                print(f"    ✓ Complete")
            else:
                print(f"    ✗ Tool '{action}' not found")
                return {"status": "failed", "step": step_num}

        return {"status": "complete", "steps": len(plan), "results": results}

# Mock tools for demonstration
tools = {
    "web_search":  lambda query: f"Search results for: {query}",
    "summarise":   lambda text: "Summary of research",
    "create_report": lambda summary, title: f"Report: {title}",
}

planner = SequentialPlanner(tools)
plan = planner.create_plan("AI frameworks comparison")
print(f"Plan created: {len(plan)} steps")
outcome = planner.execute_plan(plan)
print(f"Outcome: {outcome['status']}")