Cletus plugin kit: rules for coding agents, specification, host API, style guide, worker SDK and cletus-plugin tool

sdk/cmd/cletus-plugin/template/internal/tools/tools.go.tmpl

@@ -0,0 +1,88 @@
+// Package tools holds the plugin's chat tools.
+package tools
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+
+	"[[.SDKModule]]/pluginsdk"
+)
+
+// All returns every chat tool. Each is also listed in plugin.json.
+func All() []pluginsdk.Tool {
+	return []pluginsdk.Tool{countLines, saveSummary}
+}
+
+var pathParam = map[string]any{
+	"type": "object",
+	"properties": map[string]any{
+		"path": map[string]any{"type": "string", "description": "The text file, as the user named it."},
+	},
+	"required": []string{"path"},
+}
+
+var countLines = pluginsdk.Tool{
+	Name:        "[[.Short]]_count_lines",
+	Description: "Count the lines in a text file. Use when the user asks how long a text file is. Returns the line count.",
+	Parameters:  pathParam,
+	Run: func(ctx context.Context, h *pluginsdk.Host, call pluginsdk.ToolCall) pluginsdk.ToolResult {
+		path, lines, err := count(ctx, h, call)
+		if err != nil {
+			return pluginsdk.Fail("%v", err)
+		}
+		return pluginsdk.Text("%s has %d lines.", path, lines)
+	},
+}
+
+var saveSummary = pluginsdk.Tool{
+	Name:        "[[.Short]]_save_summary",
+	Description: "Save a one-line summary (the line count) next to a text file, as <file>.summary.txt. Use only when the user asks to save it.",
+	Parameters:  pathParam,
+	Mutating:    true,
+	Run: func(ctx context.Context, h *pluginsdk.Host, call pluginsdk.ToolCall) pluginsdk.ToolResult {
+		path, lines, err := count(ctx, h, call)
+		if err != nil {
+			return pluginsdk.Fail("%v", err)
+		}
+		out := path + ".summary.txt"
+		allowed, err := h.CanWrite(ctx, out)
+		if err != nil {
+			return pluginsdk.Fail("%v", err)
+		}
+		if !allowed || !call.EditMode {
+			return pluginsdk.Fail("Cletus doesn't allow edits in this folder. Ask the user to allow edits, then try again.")
+		}
+		if err := os.WriteFile(out, []byte(fmt.Sprintf("%d lines\n", lines)), 0o644); err != nil {
+			return pluginsdk.Fail("Couldn't save the summary: %v", err)
+		}
+		return pluginsdk.Text("Saved %s.", out)
+	},
+}
+
+// count resolves the path through the host and counts its lines.
+func count(ctx context.Context, h *pluginsdk.Host, call pluginsdk.ToolCall) (string, int, error) {
+	var args struct {
+		Path string `json:"path"`
+	}
+	if err := call.Decode(&args); err != nil {
+		return "", 0, err
+	}
+	if args.Path == "" {
+		return "", 0, fmt.Errorf("give the path of a text file")
+	}
+	path, err := h.ResolvePath(ctx, args.Path)
+	if err != nil {
+		return "", 0, err
+	}
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return "", 0, fmt.Errorf("couldn't read %s: %v", args.Path, err)
+	}
+	lines := bytes.Count(data, []byte("\n"))
+	if len(data) > 0 && data[len(data)-1] != '\n' {
+		lines++
+	}
+	return path, lines, nil
+}