新增 recall_memory 回忆工具：按 token 搜索长期记忆

internal/tools/builtin/recall_tool.go

@@ -0,0 +1,84 @@
+package builtin
+
+import (
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"myaibot/internal/store"
+	"myaibot/internal/tokens"
+)
+
+type recallTool struct {
+	db      *sql.DB
+	enabled bool
+	prompt  string
+}
+
+func NewRecallTool(db *sql.DB) *recallTool {
+	return &recallTool{
+		db:      db,
+		enabled: true,
+		prompt:  "从长期记忆中回忆与用户提问相关的信息。当用户询问个人偏好、个人信息、之前聊过的话题或需要回顾历史对话时调用此工具",
+	}
+}
+
+func (t *recallTool) Name() string        { return "recall_memory" }
+func (t *recallTool) Description() string { return t.prompt }
+func (t *recallTool) Enabled() bool       { return t.enabled }
+func (t *recallTool) DefaultConfig() map[string]any {
+	return map[string]any{"enabled": true, "prompt": t.prompt}
+}
+
+func (t *recallTool) Configure(cfg map[string]any) error {
+	var err error
+	if t.enabled, err = parseEnabled(cfg); err != nil {
+		return err
+	}
+	if p, ok := cfg["prompt"].(string); ok && p != "" {
+		t.prompt = p
+	}
+	return nil
+}
+
+func (t *recallTool) Parameters() map[string]any {
+	return map[string]any{
+		"type": "object",
+		"properties": map[string]any{
+			"query": map[string]any{"type": "string", "description": "要回忆的内容或用户的提问"},
+			"limit": map[string]any{"type": "integer", "description": "最多返回的记忆条数，默认 5，最大 10"},
+		},
+		"required": []string{"query"},
+	}
+}
+
+func (t *recallTool) Execute(args json.RawMessage) (string, error) {
+	var p struct {
+		Query string `json:"query"`
+		Limit int    `json:"limit"`
+	}
+	if err := json.Unmarshal(args, &p); err != nil {
+		return "", err
+	}
+	query := strings.TrimSpace(p.Query)
+	if query == "" {
+		return "", fmt.Errorf("query 不能为空")
+	}
+	if p.Limit == 0 {
+		p.Limit = 5
+	}
+	memories, err := store.SearchMemoriesByTokens(t.db, tokens.Tokenize(query), p.Limit)
+	if err != nil {
+		return "", err
+	}
+	if len(memories) == 0 {
+		return "未找到相关记忆", nil
+	}
+	var sb strings.Builder
+	fmt.Fprintf(&sb, "找到 %d 条相关记忆：\n", len(memories))
+	for _, m := range memories {
+		fmt.Fprintf(&sb, "- [%s %d] %s\n", m.Category, m.Importance, m.Content)
+	}
+	return strings.TrimSuffix(sb.String(), "\n"), nil
+}