feat: consistent input validation with tool execution errors

go.mod

@@ -4,26 +4,28 @@ go 1.25.0
 
 require (
 	github.com/google/go-querystring v1.1.0
+	github.com/google/jsonschema-go v0.4.2
 	github.com/google/uuid v1.6.0
-	github.com/modelcontextprotocol/go-sdk v1.1.0
+	github.com/modelcontextprotocol/go-sdk v1.5.0
 	github.com/spf13/pflag v1.0.10
 	github.com/spf13/viper v1.21.0
 )
 
 require (
 	github.com/fsnotify/fsnotify v1.9.0 // indirect
 	github.com/go-viper/mapstructure/v2 v2.4.0 // indirect
-	github.com/google/jsonschema-go v0.3.0 // indirect
 	github.com/pelletier/go-toml/v2 v2.2.4 // indirect
 	github.com/rogpeppe/go-internal v1.10.0 // indirect
 	github.com/sagikazarmark/locafero v0.12.0 // indirect
+	github.com/segmentio/asm v1.1.3 // indirect
+	github.com/segmentio/encoding v0.5.4 // indirect
 	github.com/spf13/afero v1.15.0 // indirect
 	github.com/spf13/cast v1.10.0 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
 	github.com/yosida95/uritemplate/v3 v3.0.2 // indirect
 	go.yaml.in/yaml/v3 v3.0.4 // indirect
-	golang.org/x/oauth2 v0.34.0 // indirect
-	golang.org/x/sys v0.39.0 // indirect
+	golang.org/x/oauth2 v0.35.0 // indirect
+	golang.org/x/sys v0.41.0 // indirect
 	golang.org/x/text v0.32.0 // indirect
 	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
 )

go.sum

@@ -6,13 +6,15 @@ github.com/fsnotify/fsnotify v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S
 github.com/fsnotify/fsnotify v1.9.0/go.mod h1:8jBTzvmWwFyi3Pb8djgCCO5IBqzKJ/Jwo8TRcHyHii0=
 github.com/go-viper/mapstructure/v2 v2.4.0 h1:EBsztssimR/CONLSZZ04E8qAkxNYq4Qp9LvH92wZUgs=
 github.com/go-viper/mapstructure/v2 v2.4.0/go.mod h1:oJDH3BJKyqBA2TXFhDsKDGDTlndYOZ6rGS0BRZIxGhM=
+github.com/golang-jwt/jwt/v5 v5.3.1 h1:kYf81DTWFe7t+1VvL7eS+jKFVWaUnK9cB1qbwn63YCY=
+github.com/golang-jwt/jwt/v5 v5.3.1/go.mod h1:fxCRLWMO43lRc8nhHWY6LGqRcf+1gQWArsqaEUEa5bE=
 github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
 github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
 github.com/google/go-querystring v1.1.0 h1:AnCroh3fv4ZBgVIf1Iwtovgjaw/GiKJo8M8yD/fhyJ8=
 github.com/google/go-querystring v1.1.0/go.mod h1:Kcdr2DB4koayq7X8pmAG4sNG59So17icRSOU623lUBU=
-github.com/google/jsonschema-go v0.3.0 h1:6AH2TxVNtk3IlvkkhjrtbUc4S8AvO0Xii0DxIygDg+Q=
-github.com/google/jsonschema-go v0.3.0/go.mod h1:r5quNTdLOYEz95Ru18zA0ydNbBuYoo9tgaYcxEYhJVE=
+github.com/google/jsonschema-go v0.4.2 h1:tmrUohrwoLZZS/P3x7ex0WAVknEkBZM46iALbcqoRA8=
+github.com/google/jsonschema-go v0.4.2/go.mod h1:r5quNTdLOYEz95Ru18zA0ydNbBuYoo9tgaYcxEYhJVE=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
@@ -22,8 +24,8 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
-github.com/modelcontextprotocol/go-sdk v1.1.0 h1:Qjayg53dnKC4UZ+792W21e4BpwEZBzwgRW6LrjLWSwA=
-github.com/modelcontextprotocol/go-sdk v1.1.0/go.mod h1:6fM3LCm3yV7pAs8isnKLn07oKtB0MP9LHd3DfAcKw10=
+github.com/modelcontextprotocol/go-sdk v1.5.0 h1:CHU0FIX9kpueNkxuYtfYQn1Z0slhFzBZuq+x6IiblIU=
+github.com/modelcontextprotocol/go-sdk v1.5.0/go.mod h1:gggDIhoemhWs3BGkGwd1umzEXCEMMvAnhTrnbXJKKKA=
 github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
 github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -32,6 +34,10 @@ github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjR
 github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
 github.com/sagikazarmark/locafero v0.12.0 h1:/NQhBAkUb4+fH1jivKHWusDYFjMOOKU88eegjfxfHb4=
 github.com/sagikazarmark/locafero v0.12.0/go.mod h1:sZh36u/YSZ918v0Io+U9ogLYQJ9tLLBmM4eneO6WwsI=
+github.com/segmentio/asm v1.1.3 h1:WM03sfUOENvvKexOLp+pCqgb/WDjsi7EK8gIsICtzhc=
+github.com/segmentio/asm v1.1.3/go.mod h1:Ld3L4ZXGNcSLRg4JBsZ3//1+f/TjYl0Mzen/DQy1EJg=
+github.com/segmentio/encoding v0.5.4 h1:OW1VRern8Nw6ITAtwSZ7Idrl3MXCFwXHPgqESYfvNt0=
+github.com/segmentio/encoding v0.5.4/go.mod h1:HS1ZKa3kSN32ZHVZ7ZLPLXWvOVIiZtyJnO1gPH1sKt0=
 github.com/spf13/afero v1.15.0 h1:b/YBCLWAJdFWJTN9cLhiXXcD7mzKn9Dm86dNnfyQw1I=
 github.com/spf13/afero v1.15.0/go.mod h1:NC2ByUVxtQs4b3sIUphxK0NioZnmxgyCrfzeuq8lxMg=
 github.com/spf13/cast v1.10.0 h1:h2x0u2shc1QuLHfxi+cTJvs30+ZAHOGRic8uyGTDWxY=
@@ -48,14 +54,14 @@ github.com/yosida95/uritemplate/v3 v3.0.2 h1:Ed3Oyj9yrmi9087+NczuL5BwkIc4wvTb5zI
 github.com/yosida95/uritemplate/v3 v3.0.2/go.mod h1:ILOh0sOhIJR3+L/8afwt/kE++YT040gmv5BQTMR2HP4=
 go.yaml.in/yaml/v3 v3.0.4 h1:tfq32ie2Jv2UxXFdLJdh3jXuOzWiL1fo0bu/FbuKpbc=
 go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
-golang.org/x/oauth2 v0.34.0 h1:hqK/t4AKgbqWkdkcAeI8XLmbK+4m4G5YeQRrmiotGlw=
-golang.org/x/oauth2 v0.34.0/go.mod h1:lzm5WQJQwKZ3nwavOZ3IS5Aulzxi68dUSgRHujetwEA=
-golang.org/x/sys v0.39.0 h1:CvCKL8MeisomCi6qNZ+wbb0DN9E5AATixKsvNtMoMFk=
-golang.org/x/sys v0.39.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+golang.org/x/oauth2 v0.35.0 h1:Mv2mzuHuZuY2+bkyWXIHMfhNdJAdwW3FuWeCPYN5GVQ=
+golang.org/x/oauth2 v0.35.0/go.mod h1:lzm5WQJQwKZ3nwavOZ3IS5Aulzxi68dUSgRHujetwEA=
+golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
+golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
 golang.org/x/text v0.32.0 h1:ZD01bjUt1FQ9WJ0ClOL5vxgxOI/sVCNgX1YtKwcY0mU=
 golang.org/x/text v0.32.0/go.mod h1:o/rUWzghvpD5TXrTIBuJU77MTaN0ljMWE47kxGJQ7jY=
-golang.org/x/tools v0.39.0 h1:ik4ho21kwuQln40uelmciQPp9SipgNDdrafrYA4TmQQ=
-golang.org/x/tools v0.39.0/go.mod h1:JnefbkDPyD8UU2kI5fuf8ZX4/yUeh9W877ZeBONxUqQ=
+golang.org/x/tools v0.42.0 h1:uNgphsn75Tdz5Ji2q36v/nsFSfR/9BRFvqhGBaJGd5k=
+golang.org/x/tools v0.42.0/go.mod h1:Ma6lCIwGZvHK6XtgbswSoWroEkhugApmsXyrUmBhfr0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=

pkg/chip/server_test.go

@@ -3,6 +3,7 @@ package chip
 import (
 	"context"
 	"log"
+	"strings"
 	"testing"
 
 	"github.com/modelcontextprotocol/go-sdk/mcp"
@@ -30,6 +31,52 @@ func handleTool() ToolHandlerFunc[toolInput, toolOutput] {
 	}
 }
 
+func TestTool_SchemaValidationReturnsToolExecutionError(t *testing.T) {
+	chipServer := NewServer()
+	RegisterTool[toolInput, toolOutput](chipServer, newTool())
+	chipSession := newChipSession(t.Context(), chipServer)
+	defer closeSilently(chipSession)
+
+	res, err := chipSession.CallTool(t.Context(), &mcp.CallToolParams{
+		Name:      "the_tool",
+		Arguments: map[string]any{},
+	})
+	if err != nil {
+		t.Fatalf("expected tool execution error, got protocol error: %v", err)
+	}
+	if !res.IsError {
+		t.Fatal("expected isError: true for missing required field")
+	}
+	if len(res.Content) == 0 {
+		t.Fatal("expected content describing the validation failure")
+	}
+	text, ok := res.Content[0].(*mcp.TextContent)
+	if !ok {
+		t.Fatalf("expected TextContent, got %T", res.Content[0])
+	}
+	if !strings.Contains(text.Text, "input") {
+		t.Fatalf("expected error mentioning missing field 'input', got %q", text.Text)
+	}
+}
+
+func TestTool_WrongTypeReturnsToolExecutionError(t *testing.T) {
+	chipServer := NewServer()
+	RegisterTool[toolInput, toolOutput](chipServer, newTool())
+	chipSession := newChipSession(t.Context(), chipServer)
+	defer closeSilently(chipSession)
+
+	res, err := chipSession.CallTool(t.Context(), &mcp.CallToolParams{
+		Name:      "the_tool",
+		Arguments: map[string]any{"input": 123},
+	})
+	if err != nil {
+		t.Fatalf("expected tool execution error, got protocol error: %v", err)
+	}
+	if !res.IsError {
+		t.Fatal("expected isError: true for wrong-typed field")
+	}
+}
+
 func TestTool_IgnoreUnknownFields(t *testing.T) {
 	chipServer := NewServer()
 	RegisterTool[toolInput, toolOutput](chipServer, newTool())

pkg/tools/add_business_term/tool.go

@@ -2,10 +2,12 @@ package add_business_term
 
 import (
 	"context"
+	"fmt"
 	"net/http"
 
 	"github.com/collibra/chip/pkg/chip"
 	"github.com/collibra/chip/pkg/clients"
+	"github.com/collibra/chip/pkg/tools/validation"
 	"github.com/modelcontextprotocol/go-sdk/mcp"
 )
 
@@ -48,6 +50,15 @@ func NewTool(collibraClient *http.Client) *chip.Tool[Input, Output] {
 
 func handler(collibraClient *http.Client) chip.ToolHandlerFunc[Input, Output] {
 	return func(ctx context.Context, input Input) (Output, error) {
+		if err := validation.UUID("domainId", input.DomainId); err != nil {
+			return Output{}, err
+		}
+		for i, attr := range input.Attributes {
+			if err := validation.UUID(fmt.Sprintf("attributes[%d].typeId", i), attr.TypeId); err != nil {
+				return Output{}, err
+			}
+		}
+
 		// Step 1: Create the business term asset
 		assetResp, err := clients.CreateBusinessTermAsset(ctx, collibraClient, clients.AddBusinessTermAssetRequest{
 			Name:         input.Name,

pkg/tools/add_business_term/tool_test.go

@@ -20,8 +20,8 @@ func TestAddBusinessTermSuccess(t *testing.T) {
 		if req.TypePublicId != "BusinessTerm" {
 			t.Errorf("expected typePublicId 'BusinessTerm', got '%s'", req.TypePublicId)
 		}
-		if req.DomainId != "domain-uuid-123" {
-			t.Errorf("expected domainId 'domain-uuid-123', got '%s'", req.DomainId)
+		if req.DomainId != "00000000-0000-0000-0000-000000000123" {
+			t.Errorf("expected domainId '00000000-0000-0000-0000-000000000123', got '%s'", req.DomainId)
 		}
 		return http.StatusCreated, clients.AddBusinessTermAssetResponse{Id: "new-asset-uuid-456"}
 	}))
@@ -45,7 +45,7 @@ func TestAddBusinessTermSuccess(t *testing.T) {
 	client := testutil.NewClient(server)
 	output, err := add_business_term.NewTool(client).Handler(t.Context(), add_business_term.Input{
 		Name:       "Revenue",
-		DomainId:   "domain-uuid-123",
+		DomainId:   "00000000-0000-0000-0000-000000000123",
 		Definition: "Total income generated from sales",
 	})
 	if err != nil {
@@ -97,7 +97,7 @@ func TestAddBusinessTermNoDefinitionNoAttributes(t *testing.T) {
 	client := testutil.NewClient(server)
 	output, err := add_business_term.NewTool(client).Handler(t.Context(), add_business_term.Input{
 		Name:     "Simple Term",
-		DomainId: "domain-uuid-456",
+		DomainId: "00000000-0000-0000-0000-000000000456",
 	})
 	if err != nil {
 		t.Fatalf("expected no error, got: %v", err)
@@ -132,11 +132,11 @@ func TestAddBusinessTermWithAdditionalAttributes(t *testing.T) {
 	client := testutil.NewClient(server)
 	output, err := add_business_term.NewTool(client).Handler(t.Context(), add_business_term.Input{
 		Name:       "Complex Term",
-		DomainId:   "domain-uuid-789",
+		DomainId:   "00000000-0000-0000-0000-000000000789",
 		Definition: "A complex business term",
 		Attributes: []add_business_term.InputAttribute{
-			{TypeId: "custom-type-1", Value: "custom value 1"},
-			{TypeId: "custom-type-2", Value: "custom value 2"},
+			{TypeId: "00000000-0000-0000-0000-0000000000c1", Value: "custom value 1"},
+			{TypeId: "00000000-0000-0000-0000-0000000000c2", Value: "custom value 2"},
 		},
 	})
 	if err != nil {
@@ -169,7 +169,7 @@ func TestAddBusinessTermAttributeCreationError(t *testing.T) {
 	client := testutil.NewClient(server)
 	_, err := add_business_term.NewTool(client).Handler(t.Context(), add_business_term.Input{
 		Name:       "Failing Term",
-		DomainId:   "domain-uuid-123",
+		DomainId:   "00000000-0000-0000-0000-000000000123",
 		Definition: "This should fail on attribute creation",
 	})
 	if err == nil {

pkg/tools/add_data_classification_match/tool.go

@@ -4,10 +4,10 @@ import (
 	"context"
 	"fmt"
 	"net/http"
-	"strings"
 
 	"github.com/collibra/chip/pkg/chip"
 	"github.com/collibra/chip/pkg/clients"
+	"github.com/collibra/chip/pkg/tools/validation"
 	"github.com/modelcontextprotocol/go-sdk/mcp"
 )
 
@@ -34,9 +34,11 @@ func NewTool(collibraClient *http.Client) *chip.Tool[Input, Output] {
 
 func handler(collibraClient *http.Client) chip.ToolHandlerFunc[Input, Output] {
 	return func(ctx context.Context, input Input) (Output, error) {
-		output, isNotValid := validateInput(input)
-		if isNotValid {
-			return output, nil
+		if err := validation.UUID("assetId", input.AssetID); err != nil {
+			return Output{}, err
+		}
+		if err := validation.UUID("classificationId", input.ClassificationID); err != nil {
+			return Output{}, err
 		}
 
 		request := clients.AddDataClassificationMatchRequest{
@@ -58,21 +60,3 @@ func handler(collibraClient *http.Client) chip.ToolHandlerFunc[Input, Output] {
 		}, nil
 	}
 }
-
-func validateInput(input Input) (Output, bool) {
-	if strings.TrimSpace(input.AssetID) == "" {
-		return Output{
-			Success: false,
-			Error:   "Asset ID is required",
-		}, true
-	}
-
-	if strings.TrimSpace(input.ClassificationID) == "" {
-		return Output{
-			Success: false,
-			Error:   "Classification ID is required",
-		}, true
-	}
-
-	return Output{}, false
-}

pkg/tools/add_data_classification_match/tool_test.go

@@ -81,18 +81,9 @@ func TestAddClassificationMatch_MissingAssetID(t *testing.T) {
 		ClassificationID: "be45c001-b173-48ff-ac91-3f6e45868c8b",
 	}
 
-	output, err := tools.NewTool(client).Handler(t.Context(), input)
-
-	if err != nil {
-		t.Fatalf("Expected no error, got %v", err)
-	}
-
-	if output.Success {
-		t.Error("Expected success=false for missing asset ID")
-	}
-
-	if output.Error == "" {
-		t.Error("Expected error message for missing asset ID")
+	_, err := tools.NewTool(client).Handler(t.Context(), input)
+	if err == nil {
+		t.Fatal("Expected UUID validation error, got nil")
 	}
 }
 
@@ -103,18 +94,9 @@ func TestAddClassificationMatch_MissingClassificationID(t *testing.T) {
 		AssetID: "9179b887-04ef-4ce5-ab3a-b5bbd39ea3c8",
 	}
 
-	output, err := tools.NewTool(client).Handler(t.Context(), input)
-
-	if err != nil {
-		t.Fatalf("Expected no error, got %v", err)
-	}
-
-	if output.Success {
-		t.Error("Expected success=false for missing classification ID")
-	}
-
-	if output.Error == "" {
-		t.Error("Expected error message for missing classification ID")
+	_, err := tools.NewTool(client).Handler(t.Context(), input)
+	if err == nil {
+		t.Fatal("Expected UUID validation error, got nil")
 	}
 }
 

pkg/tools/create_asset/tool.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/collibra/chip/pkg/chip"
 	"github.com/collibra/chip/pkg/clients"
+	"github.com/collibra/chip/pkg/tools/validation"
 	"github.com/modelcontextprotocol/go-sdk/mcp"
 )
 
@@ -37,6 +38,18 @@ func NewTool(collibraClient *http.Client) *chip.Tool[Input, Output] {
 
 func handler(collibraClient *http.Client) chip.ToolHandlerFunc[Input, Output] {
 	return func(ctx context.Context, input Input) (Output, error) {
+		if err := validation.UUID("assetTypeId", input.AssetTypeID); err != nil {
+			return Output{}, err
+		}
+		if err := validation.UUID("domainId", input.DomainID); err != nil {
+			return Output{}, err
+		}
+		for typeID := range input.Attributes {
+			if err := validation.UUID(fmt.Sprintf("attributes[%q]", typeID), typeID); err != nil {
+				return Output{}, err
+			}
+		}
+
 		// Create the asset
 		assetReq := clients.CreateAssetRequest{
 			Name:        input.Name,