Merge pull request #696 from tonybaloney/cookbook/ralph-loop-recipe

Add RALPH-loop recipes to Copilot SDK cookbook

cookbook/copilot-sdk/go/recipe/ralph-loop.go

@@ -0,0 +1,111 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+
+	copilot "github.com/github/copilot-sdk/go"
+)
+
+// Ralph loop: autonomous AI task loop with fresh context per iteration.
+//
+// Two modes:
+//   - "plan": reads PROMPT_plan.md, generates/updates IMPLEMENTATION_PLAN.md
+//   - "build": reads PROMPT_build.md, implements tasks, runs tests, commits
+//
+// Each iteration creates a fresh session so the agent always operates in
+// the "smart zone" of its context window. State is shared between
+// iterations via files on disk (IMPLEMENTATION_PLAN.md, AGENTS.md, specs/*).
+//
+// Usage:
+//   go run ralph-loop.go              # build mode, 50 iterations
+//   go run ralph-loop.go plan         # planning mode
+//   go run ralph-loop.go 20           # build mode, 20 iterations
+//   go run ralph-loop.go plan 5       # planning mode, 5 iterations
+
+func ralphLoop(ctx context.Context, mode string, maxIterations int) error {
+	promptFile := "PROMPT_build.md"
+	if mode == "plan" {
+		promptFile = "PROMPT_plan.md"
+	}
+
+	client := copilot.NewClient(nil)
+	if err := client.Start(ctx); err != nil {
+		return fmt.Errorf("failed to start client: %w", err)
+	}
+	defer client.Stop()
+
+	cwd, err := os.Getwd()
+	if err != nil {
+		return fmt.Errorf("failed to get working directory: %w", err)
+	}
+
+	fmt.Println(strings.Repeat("━", 40))
+	fmt.Printf("Mode:   %s\n", mode)
+	fmt.Printf("Prompt: %s\n", promptFile)
+	fmt.Printf("Max:    %d iterations\n", maxIterations)
+	fmt.Println(strings.Repeat("━", 40))
+
+	prompt, err := os.ReadFile(promptFile)
+	if err != nil {
+		return fmt.Errorf("failed to read %s: %w", promptFile, err)
+	}
+
+	for i := 1; i <= maxIterations; i++ {
+		fmt.Printf("\n=== Iteration %d/%d ===\n", i, maxIterations)
+
+		session, err := client.CreateSession(ctx, &copilot.SessionConfig{
+			Model:            "gpt-5.1-codex-mini",
+			WorkingDirectory: cwd,
+			OnPermissionRequest: func(_ copilot.PermissionRequest, _ map[string]string) copilot.PermissionRequestResult {
+				return copilot.PermissionRequestResult{Kind: "approved"}
+			},
+		})
+		if err != nil {
+			return fmt.Errorf("failed to create session: %w", err)
+		}
+
+		// Log tool usage for visibility
+		session.On(func(event copilot.Event) {
+			if toolExecution, ok := event.(copilot.ToolExecutionStartEvent); ok {
+				fmt.Printf("  ⚙ %s\n", toolExecution.Data.ToolName)
+			}
+		})
+
+		_, err = session.SendAndWait(ctx, copilot.MessageOptions{
+			Prompt: string(prompt),
+		})
+		if destroyErr := session.Destroy(); destroyErr != nil {
+			log.Printf("failed to destroy session on iteration %d: %v", i, destroyErr)
+		}
+		if err != nil {
+			return fmt.Errorf("send failed on iteration %d: %w", i, err)
+		}
+
+		fmt.Printf("\nIteration %d complete.\n", i)
+	}
+
+	fmt.Printf("\nReached max iterations: %d\n", maxIterations)
+	return nil
+}
+
+func main() {
+	mode := "build"
+	maxIterations := 50
+
+	for _, arg := range os.Args[1:] {
+		if arg == "plan" {
+			mode = "plan"
+		} else if n, err := strconv.Atoi(arg); err == nil {
+			maxIterations = n
+		}
+	}
+
+	if err := ralphLoop(context.Background(), mode, maxIterations); err != nil {
+		log.Fatal(err)
+	}
+}