diff --git a/.github/workflows/go-ci.yml b/.github/workflows/go.yml
similarity index 61%
rename from .github/workflows/go-ci.yml
rename to .github/workflows/go.yml
index 4ed4194..4dff470 100644
--- a/.github/workflows/go-ci.yml
+++ b/.github/workflows/go.yml
@@ -1,22 +1,19 @@
-name: go-ci
+name: Go
 on:
   push:
-    branches:
-      - main
+    branches: main
   pull_request:
-    branches:
-      - main
+    branches: ["*"]
 
 permissions:
   contents: read
-  pull-requests: read
 
 jobs:
-  golangci:
+  lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
-      - uses: actions/setup-go@v4
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
         with:
           go-version: "1.21"
           check-latest: true
@@ -27,10 +24,10 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
-      - uses: actions/setup-go@v4
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
         with:
           go-version: "1.21"
           check-latest: true
       - name: Test
-        run: go test -v ./...
+        run: go test -v
diff --git a/.golangci.yml b/.golangci.yml
new file mode 100644
index 0000000..db04bab
--- /dev/null
+++ b/.golangci.yml
@@ -0,0 +1,24 @@
+output:
+  sort-results: true
+
+linters:
+  enable:
+    - gofumpt
+    - nolintlint
+    - paralleltest
+    - revive
+
+linters-settings:
+  govet:
+    enable-all: true
+    disable:
+      - fieldalignment
+
+  errcheck:
+    exclude-functions:
+      - (io.Closer).Close
+
+issues:
+  exclude-use-default: false
+  max-issues-per-linter: 0
+  max-same-issues: 0
diff --git a/filter.go b/filter.go
index b83dbf0..7d455af 100644
--- a/filter.go
+++ b/filter.go
@@ -144,11 +144,11 @@ func processNonNumberedAspectFilter(params map[string]string) ([]aspectFilter, e
 	if err != nil {
 		return nil, err
 	}
-	filter := aspectFilter{
+	flt := aspectFilter{
 		aspectName:       params["aspectFilter.aspectName"],
 		aspectValueNames: filterValues,
 	}
-	return []aspectFilter{filter}, nil
+	return []aspectFilter{flt}, nil
 }
 
 func processNumberedAspectFilters(params map[string]string) ([]aspectFilter, error) {
@@ -162,11 +162,11 @@ func processNumberedAspectFilters(params map[string]string) ([]aspectFilter, err
 		if err != nil {
 			return nil, err
 		}
-		aspectFilter := aspectFilter{
+		flt := aspectFilter{
 			aspectName:       name,
 			aspectValueNames: filterValues,
 		}
-		aspectFilters = append(aspectFilters, aspectFilter)
+		aspectFilters = append(aspectFilters, flt)
 	}
 	return aspectFilters, nil
 }
@@ -188,7 +188,7 @@ func processNonNumberedItemFilter(params map[string]string) ([]itemFilter, error
 	if err != nil {
 		return nil, err
 	}
-	filter := itemFilter{
+	flt := itemFilter{
 		name:   params["itemFilter.name"],
 		values: filterValues,
 	}
@@ -198,13 +198,13 @@ func processNonNumberedItemFilter(params map[string]string) ([]itemFilter, error
 		return nil, ErrIncompleteItemFilterParam
 	}
 	if pnOk && pvOk {
-		filter.paramName = &pn
-		filter.paramValue = &pv
+		flt.paramName = &pn
+		flt.paramValue = &pv
 	}
-	if err = handleItemFilterType(&filter, nil, params); err != nil {
+	if err = handleItemFilterType(&flt, nil, params); err != nil {
 		return nil, err
 	}
-	return []itemFilter{filter}, nil
+	return []itemFilter{flt}, nil
 }
 
 func processNumberedItemFilters(params map[string]string) ([]itemFilter, error) {
@@ -218,7 +218,7 @@ func processNumberedItemFilters(params map[string]string) ([]itemFilter, error)
 		if err != nil {
 			return nil, err
 		}
-		itemFilter := itemFilter{
+		flt := itemFilter{
 			name:   name,
 			values: filterValues,
 		}
@@ -228,10 +228,10 @@ func processNumberedItemFilters(params map[string]string) ([]itemFilter, error)
 			return nil, ErrIncompleteItemFilterParam
 		}
 		if pnOk && pvOk {
-			itemFilter.paramName = &pn
-			itemFilter.paramValue = &pv
+			flt.paramName = &pn
+			flt.paramValue = &pv
 		}
-		itemFilters = append(itemFilters, itemFilter)
+		itemFilters = append(itemFilters, flt)
 	}
 	for i := range itemFilters {
 		if err := handleItemFilterType(&itemFilters[i], itemFilters, params); err != nil {
diff --git a/params.go b/params.go
index 2026ae3..136e9bc 100644
--- a/params.go
+++ b/params.go
@@ -243,7 +243,7 @@ func (fp *findItemsByCategoryParams) validate(params map[string]string) error {
 	fp.categoryIDs = categoryIDs
 	globalID, ok := params["Global-ID"]
 	if ok {
-		if err := validateGlobalID(globalID); err != nil {
+		if err = validateGlobalID(globalID); err != nil {
 			return err
 		}
 		fp.globalID = &globalID
@@ -373,7 +373,7 @@ func (fp *findItemsByKeywordsParams) validate(params map[string]string) error {
 	fp.keywords = keywords
 	globalID, ok := params["Global-ID"]
 	if ok {
-		if err := validateGlobalID(globalID); err != nil {
+		if err = validateGlobalID(globalID); err != nil {
 			return err
 		}
 		fp.globalID = &globalID
@@ -671,7 +671,7 @@ func (fp *findItemsByProductParams) validate(params map[string]string) error {
 	}
 	globalID, ok := params["Global-ID"]
 	if ok {
-		if err := validateGlobalID(globalID); err != nil {
+		if err = validateGlobalID(globalID); err != nil {
 			return err
 		}
 		fp.globalID = &globalID
diff --git a/response.go b/response.go
index eeeff7a..b78867f 100644
--- a/response.go
+++ b/response.go
@@ -7,7 +7,7 @@ import "time"
 
 // A ResultProvider represents results from eBay Finding API endpoints.
 type ResultProvider interface {
-	// Results returns results from the eBay Finding API endpoint.
+	// Results returns results from an eBay Finding API endpoint.
 	Results() []FindItemsResponse
 }
 
@@ -16,6 +16,8 @@ type FindItemsByCategoriesResponse struct {
 	ItemsResponse []FindItemsResponse `json:"findItemsByCategoryResponse"`
 }
 
+// Results returns results from the eBay Finding API findItemsByCategory endpoint.
+// See https://developer.ebay.com/devzone/finding/CallRef/findItemsByCategory.html.
 func (r FindItemsByCategoriesResponse) Results() []FindItemsResponse {
 	return r.ItemsResponse
 }
@@ -25,6 +27,8 @@ type FindItemsByKeywordsResponse struct {
 	ItemsResponse []FindItemsResponse `json:"findItemsByKeywordsResponse"`
 }
 
+// Results returns results from the eBay Finding API findItemsByKeywords endpoint.
+// See https://developer.ebay.com/devzone/finding/CallRef/findItemsByKeywords.html.
 func (r FindItemsByKeywordsResponse) Results() []FindItemsResponse {
 	return r.ItemsResponse
 }
@@ -34,6 +38,8 @@ type FindItemsAdvancedResponse struct {
 	ItemsResponse []FindItemsResponse `json:"findItemsAdvancedResponse"`
 }
 
+// Results returns results from the eBay Finding API findItemsAdvanced endpoint.
+// See https://developer.ebay.com/devzone/finding/CallRef/findItemsAdvanced.html.
 func (r FindItemsAdvancedResponse) Results() []FindItemsResponse {
 	return r.ItemsResponse
 }
@@ -43,6 +49,8 @@ type FindItemsByProductResponse struct {
 	ItemsResponse []FindItemsResponse `json:"findItemsByProductResponse"`
 }
 
+// Results returns results from the eBay Finding API findItemsByProduct endpoint.
+// See https://developer.ebay.com/devzone/finding/CallRef/findItemsByProduct.html.
 func (r FindItemsByProductResponse) Results() []FindItemsResponse {
 	return r.ItemsResponse
 }
@@ -52,6 +60,8 @@ type FindItemsInEBayStoresResponse struct {
 	ItemsResponse []FindItemsResponse `json:"findItemsIneBayStoresResponse"`
 }
 
+// Results returns results from the eBay Finding API findItemsIneBayStores endpoint.
+// See https://developer.ebay.com/devzone/finding/CallRef/findItemsIneBayStores.html.
 func (r FindItemsInEBayStoresResponse) Results() []FindItemsResponse {
 	return r.ItemsResponse
 }