refactor: an agent that can use tools to find information in Go codebases

Author: TobiasGleiter

agents/agents.go

@@ -11,9 +11,9 @@ import (
 	"errors"
 	"fmt"
 
-	"github.com/bit8bytes/gogantic/agents/tools"
 	"github.com/bit8bytes/gogantic/inputs/roles"
 	"github.com/bit8bytes/gogantic/llms"
+	"github.com/bit8bytes/gogantic/tools"
 )
 
 type llm interface {

agents/react.go

@@ -50,7 +50,9 @@ Respond with a JSON object on each turn with these fields:
 - "thought": your reasoning about what to do next
 - "action": the exact tool name to call (empty string when giving final answer)
 - "action_input": the input to pass to the tool (empty string when giving final answer)
-- "final_answer": your final answer (empty string when calling a tool)
+- "final_answer": your final answer to the user — MUST be non-empty when you are done; empty string ONLY when calling a tool
+
+When you have enough information to answer, set "action" and "action_input" to "" and put a detailed answer based on your observations — MUST be non-empty when done; be thorough and include all relevant findings.
 
 Think step by step. Do not hallucinate.`, toolDescriptions.String(), jsonInstructions),
 		},

agents/tools/tools.go

@@ -0,0 +1,92 @@
+package main
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"time"
+
+	"github.com/bit8bytes/gogantic/agents"
+	"github.com/bit8bytes/gogantic/llms/ollama"
+	"github.com/bit8bytes/gogantic/runner"
+	"github.com/bit8bytes/gogantic/stores/moderncsqlite"
+	"github.com/bit8bytes/gogantic/tools"
+)
+
+func setupDatabase(ctx context.Context) (*sql.DB, error) {
+	db, err := sql.Open("sqlite", "agent.db")
+	if err != nil {
+		return nil, err
+	}
+
+	if err := db.PingContext(ctx); err != nil {
+		return nil, err
+	}
+
+	return db, nil
+}
+
+func migrateDatabase(ctx context.Context, db *sql.DB) error {
+	_, err := db.ExecContext(ctx, `
+		CREATE TABLE IF NOT EXISTS messages (
+			id         INTEGER PRIMARY KEY AUTOINCREMENT,
+			role       TEXT NOT NULL,
+			content    TEXT NOT NULL,
+			created_at DATETIME DEFAULT CURRENT_TIMESTAMP
+		);`)
+	return err
+}
+
+func main() {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*120)
+	defer cancel()
+
+	// Omitting errors for example sake.
+	db, _ := setupDatabase(ctx)
+	defer db.Close()
+
+	_ = migrateDatabase(ctx, db)
+
+	storage, _ := moderncsqlite.New(ctx, db)
+	defer storage.Close()
+
+	model := ollama.New(ollama.Model{
+		Model:   "gemma3:12b",
+		Options: ollama.Options{NumCtx: 4096},
+		Stream:  false,
+		Format:  ollama.JSON,
+	})
+
+	// These tools are specifically designed for Golang.
+	tools := []agents.Tool{
+		tools.ListGoPackages{},
+		tools.ParseGoFile{},
+		tools.FindIdent{},
+		tools.FindCalls{},
+		tools.FindImporters{},
+		tools.FindImplementors{},
+	}
+
+	agent, err := agents.NewReAct(ctx, model, tools, storage)
+	if err != nil {
+		panic(err)
+	}
+
+	task := `
+		Find all types in this codebase that implement the parser interface.
+		For each type, show which package and file it is defined in.`
+	if err := agent.Task(ctx, task); err != nil {
+		panic(err)
+	}
+
+	r := runner.New(agent, true)
+	if err := r.Run(ctx); err != nil {
+		panic(err)
+	}
+
+	finalAnswer, err := agent.Answer()
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println(finalAnswer)
+}

examples/agents/ollama/grep/grep.go

@@ -4,6 +4,10 @@ import (
 	"github.com/bit8bytes/gogantic/llms"
 )
 
+const (
+	JSON = "json"
+)
+
 type Model struct {
 	Model     string   `json:"model"`
 	Endpoint  string   `json:"endpoint"`

examples/agents/ollama/grep/main.go

@@ -0,0 +1,35 @@
+// NOTE: This file was generated by AI and needs to be evaluated and refactored before production use.
+package tools
+
+import (
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"io/fs"
+	"path/filepath"
+	"strings"
+)
+
+func walkGoFiles(dir string, fset *token.FileSet) ([]*ast.File, error) {
+	var files []*ast.File
+	err := filepath.WalkDir(dir, func(path string, d fs.DirEntry, err error) error {
+		if err != nil || d.IsDir() || filepath.Ext(path) != ".go" {
+			return nil
+		}
+		f, parseErr := parser.ParseFile(fset, path, nil, 0)
+		if parseErr != nil {
+			return nil
+		}
+		files = append(files, f)
+		return nil
+	})
+	return files, err
+}
+
+func twoLines(s string) (first, second string, ok bool) {
+	parts := strings.SplitN(strings.TrimSpace(s), "\n", 2)
+	if len(parts) != 2 {
+		return "", "", false
+	}
+	return strings.TrimSpace(parts[0]), strings.TrimSpace(parts[1]), true
+}

examples/agents/ollama/main.go

@@ -0,0 +1,66 @@
+// NOTE: This file was generated by AI and needs to be evaluated and refactored before production use.
+package tools
+
+import (
+	"context"
+	"fmt"
+	"go/ast"
+	"go/token"
+	"strings"
+)
+
+type FindCalls struct{}
+
+func (t FindCalls) Name() string { return "FindCalls" }
+
+func (t FindCalls) Description() string {
+	return `Find all call sites of a function by name in a Go codebase.
+Matches both direct calls (f()) and method calls (obj.f()).
+Input: two lines — directory path, then function name (e.g. 'Println').`
+}
+
+func (t FindCalls) Execute(ctx context.Context, input Input) (Output, error) {
+	dir, funcName, ok := twoLines(input.Content)
+	if !ok {
+		return Output{Content: "Error: provide directory and function name on separate lines"}, nil
+	}
+
+	fset := token.NewFileSet()
+	files, err := walkGoFiles(dir, fset)
+	if err != nil {
+		return Output{Content: "Error: " + err.Error()}, nil
+	}
+
+	var b strings.Builder
+	found := 0
+	for _, f := range files {
+		ast.Inspect(f, func(n ast.Node) bool {
+			call, ok := n.(*ast.CallExpr)
+			if !ok {
+				return true
+			}
+			if callFuncName(call.Fun) == funcName {
+				pos := fset.Position(call.Pos())
+				fmt.Fprintf(&b, "%s:%d\n", pos.Filename, pos.Line)
+				found++
+			}
+			return true
+		})
+	}
+
+	if found == 0 {
+		return Output{Content: "not found"}, nil
+	}
+	return Output{Content: b.String()}, nil
+}
+
+func callFuncName(expr ast.Expr) string {
+	switch e := expr.(type) {
+	case *ast.Ident:
+		return e.Name
+	case *ast.SelectorExpr:
+		return e.Sel.Name
+	default:
+		return ""
+	}
+}