diff --git a/providers/confmap/confmap.go b/providers/confmap/confmap.go
index 9c5871a..b6415fc 100644
--- a/providers/confmap/confmap.go
+++ b/providers/confmap/confmap.go
@@ -26,7 +26,7 @@ func Provider(mp map[string]interface{}, delim string) *Confmap {
 	return &Confmap{mp: cp}
 }
 
-// ReadBytes is not supported by the env provider.
+// ReadBytes is not supported by the confmap provider.
 func (e *Confmap) ReadBytes() ([]byte, error) {
 	return nil, errors.New("confmap provider does not support this method")
 }
diff --git a/providers/consul/consul.go b/providers/consul/consul.go
index 5693b73..e6350df 100644
--- a/providers/consul/consul.go
+++ b/providers/consul/consul.go
@@ -144,7 +144,7 @@ func (c *Consul) Watch(cb func(event interface{}, err error)) error {
 		return err
 	}
 
-	plan.Handler = func(idx uint64, val interface{}) {
+	plan.Handler = func(_ uint64, val interface{}) {
 		cb(val, nil)
 	}
 
diff --git a/providers/etcd/etcd.go b/providers/etcd/etcd.go
index 11a82de..e4c989b 100644
--- a/providers/etcd/etcd.go
+++ b/providers/etcd/etcd.go
@@ -49,10 +49,12 @@ func Provider(cfg Config) *Etcd {
 	return &Etcd{client: c, cfg: cfg}
 }
 
+// ReadBytes is not supported by etcd provider.
 func (e *Etcd) ReadBytes() ([]byte, error) {
 	return nil, errors.New("etcd provider does not support this method")
 }
 
+// Read returns a nested config map.
 func (e *Etcd) Read() (map[string]interface{}, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), e.cfg.DialTimeout)
 	defer cancel()
diff --git a/providers/posflag/posflag.go b/providers/posflag/posflag.go
index d95a4f8..f28e2a3 100644
--- a/providers/posflag/posflag.go
+++ b/providers/posflag/posflag.go
@@ -6,9 +6,10 @@ package posflag
 import (
 	"errors"
 
+	"github.com/spf13/pflag"
+
 	"github.com/knadh/koanf"
 	"github.com/knadh/koanf/maps"
-	"github.com/spf13/pflag"
 )
 
 // Posflag implements a pflag command line provider.
@@ -126,7 +127,7 @@ func (p *Posflag) Read() (map[string]interface{}, error) {
 	return maps.Unflatten(mp, p.delim), nil
 }
 
-// ReadBytes is not supported by the env koanf.
+// ReadBytes is not supported by the pflag provider.
 func (p *Posflag) ReadBytes() ([]byte, error) {
 	return nil, errors.New("pflag provider does not support this method")
 }
diff --git a/providers/rawbytes/rawbytes.go b/providers/rawbytes/rawbytes.go
index 96cc0b8..9e02317 100644
--- a/providers/rawbytes/rawbytes.go
+++ b/providers/rawbytes/rawbytes.go
@@ -20,12 +20,12 @@ func Provider(b []byte) *RawBytes {
 	return r
 }
 
-// ReadBytes is not supported by the env provider.
+// ReadBytes returns the raw bytes for parsing.
 func (r *RawBytes) ReadBytes() ([]byte, error) {
 	return r.b, nil
 }
 
-// Read returns the raw bytes for parsing.
+// Read is not supported by rawbytes provider.
 func (r *RawBytes) Read() (map[string]interface{}, error) {
-	return nil, errors.New("buf provider does not support this method")
+	return nil, errors.New("rawbytes provider does not support this method")
 }
diff --git a/providers/s3/s3.go b/providers/s3/s3.go
index 0088283..13e6343 100644
--- a/providers/s3/s3.go
+++ b/providers/s3/s3.go
@@ -64,7 +64,7 @@ func (r *S3) ReadBytes() ([]byte, error) {
 	return data, nil
 }
 
-// Read returns the raw bytes for parsing.
+// Read is not supported for s3 provider.
 func (r *S3) Read() (map[string]interface{}, error) {
 	return nil, errors.New("s3 provider does not support this method")
 }
diff --git a/providers/structs/structs.go b/providers/structs/structs.go
index bff92b7..0022083 100644
--- a/providers/structs/structs.go
+++ b/providers/structs/structs.go
@@ -6,6 +6,7 @@ import (
 	"errors"
 
 	"github.com/fatih/structs"
+
 	"github.com/knadh/koanf/maps"
 )
 
@@ -16,7 +17,7 @@ type Structs struct {
 	delim string
 }
 
-// Provider returns a provider that takes a  takes a struct and a struct tag
+// Provider returns a provider that takes a takes a struct and a struct tag
 // and uses structs to parse and provide it to koanf.
 func Provider(s interface{}, tag string) *Structs {
 	return &Structs{s: s, tag: tag}
diff --git a/providers/vault/vault.go b/providers/vault/vault.go
index 6150af7..2307c10 100644
--- a/providers/vault/vault.go
+++ b/providers/vault/vault.go
@@ -8,6 +8,7 @@ import (
 	"time"
 
 	"github.com/hashicorp/vault/api"
+
 	"github.com/knadh/koanf/maps"
 )
 
@@ -40,6 +41,7 @@ type Vault struct {
 	cfg    Config
 }
 
+// Provider returns a provider that takes a Vault config.
 func Provider(cfg Config) *Vault {
 	httpClient := &http.Client{Timeout: cfg.Timeout}
 	client, err := api.NewClient(&api.Config{Address: cfg.Address, HttpClient: httpClient})
@@ -51,10 +53,12 @@ func Provider(cfg Config) *Vault {
 	return &Vault{client: client, cfg: cfg}
 }
 
+// ReadBytes is not supported by the vault provider.
 func (r *Vault) ReadBytes() ([]byte, error) {
 	return nil, errors.New("vault provider does not support this method")
 }
 
+// Read fetches the configuration from the source and returns a nested config map.
 func (r *Vault) Read() (map[string]interface{}, error) {
 	secret, err := r.client.Logical().Read(r.cfg.Path)
 	if err != nil {