Added request/response validation
diff --git a/tools/search.go b/tools/search.go
index c96f407..2a78f8e 100644
--- a/tools/search.go
+++ b/tools/search.go
@@ -6,19 +6,22 @@
 	"strings"
 
 	"github.com/korap/korap-mcp/service"
+	"github.com/korap/korap-mcp/validation"
 	"github.com/mark3labs/mcp-go/mcp"
 	"github.com/rs/zerolog/log"
 )
 
 // SearchTool implements the Tool interface for KorAP corpus search
 type SearchTool struct {
-	client *service.Client
+	client    *service.Client
+	validator *validation.Validator
 }
 
 // NewSearchTool creates a new search tool instance
 func NewSearchTool(client *service.Client) *SearchTool {
 	return &SearchTool{
-		client: client,
+		client:    client,
+		validator: validation.New(log.Logger),
 	}
 }
 
@@ -80,12 +83,34 @@
 	corpus := request.GetString("corpus", "")
 	count := request.GetInt("count", 25)
 
+	// Validate the search request using the validation package
+	searchReq := validation.SearchRequest{
+		Query:         query,
+		QueryLanguage: queryLang,
+		Corpus:        corpus,
+		Count:         count,
+	}
+
+	if err := s.validator.ValidateSearchRequest(searchReq); err != nil {
+		log.Warn().
+			Err(err).
+			Interface("request", searchReq).
+			Msg("Search request validation failed")
+		return nil, fmt.Errorf("invalid search request: %w", err)
+	}
+
+	// Sanitize inputs
+	query = s.validator.SanitizeQuery(query)
+	if corpus != "" {
+		corpus = s.validator.SanitizeCorpusID(corpus)
+	}
+
 	log.Debug().
 		Str("query", query).
 		Str("query_language", queryLang).
 		Str("corpus", corpus).
 		Int("count", count).
-		Msg("Parsed search parameters")
+		Msg("Parsed and validated search parameters")
 
 	// Check if client is available and authenticated
 	if s.client == nil {
@@ -100,7 +125,7 @@
 	}
 
 	// Prepare search request
-	searchReq := service.SearchRequest{
+	korapSearchReq := service.SearchRequest{
 		Query:      query,
 		QueryLang:  queryLang,
 		Collection: corpus,
@@ -109,7 +134,7 @@
 
 	// Perform the search
 	var searchResp service.SearchResponse
-	err = s.client.PostJSON(ctx, "search", searchReq, &searchResp)
+	err = s.client.PostJSON(ctx, "search", korapSearchReq, &searchResp)
 	if err != nil {
 		log.Error().
 			Err(err).
@@ -118,6 +143,14 @@
 		return nil, fmt.Errorf("search failed: %w", err)
 	}
 
+	// Validate the response
+	if err := s.validator.ValidateSearchResponse(&searchResp); err != nil {
+		log.Warn().
+			Err(err).
+			Msg("Search response validation failed, but continuing with potentially invalid data")
+		// Continue processing despite validation errors to be resilient
+	}
+
 	log.Info().
 		Str("query", query).
 		Int("total_results", searchResp.Meta.TotalResults).