diff --git a/src/tr31-tool.c b/src/tr31-tool.c
index d0d1579..2d195f0 100644
--- a/src/tr31-tool.c
+++ b/src/tr31-tool.c
@@ -791,7 +791,7 @@ static int do_tr31_import(const struct tr31_tool_options_t* options)
 	);
 	printf("Key algorithm: [%c] %s\n",
 		tr31_ctx.key.algorithm,
-		tr31_key_algorithm_get_desc(&tr31_ctx, tr31_ctx.key.algorithm)
+		tr31_key_algorithm_get_desc(&tr31_ctx)
 	);
 	printf("Key mode of use: [%c] %s\n",
 		tr31_ctx.key.mode_of_use,
@@ -804,11 +804,11 @@ static int do_tr31_import(const struct tr31_tool_options_t* options)
 	}
 	printf("Key exportability: [%c] %s\n",
 		tr31_ctx.key.exportability,
-		tr31_key_exportability_get_desc(tr31_ctx.key.exportability)
+		tr31_key_exportability_get_desc(&tr31_ctx)
 	);
 	printf("Key context: [%c] %s\n",
 		tr31_ctx.key.key_context,
-		tr31_key_context_get_desc(tr31_ctx.key.key_context)
+		tr31_key_context_get_desc(&tr31_ctx)
 	);
 
 	// print optional blocks, if available
diff --git a/src/tr31_strings.c b/src/tr31_strings.c
index 81e9f8e..0bfad20 100644
--- a/src/tr31_strings.c
+++ b/src/tr31_strings.c
@@ -164,15 +164,19 @@ const char* tr31_key_usage_get_desc(const struct tr31_ctx_t* ctx)
 	return "Unknown key usage value";
 }
 
-const char* tr31_key_algorithm_get_desc(const struct tr31_ctx_t* ctx, unsigned int algorithm)
+const char* tr31_key_algorithm_get_desc(const struct tr31_ctx_t* ctx)
 {
+	if (!ctx) {
+		return NULL;
+	}
+
 	// See ANSI X9.143:2021, 6.3.2, table 3
 	// See ISO 20038:2017, Annex A.2.4, table A.4
-	switch (algorithm) {
+	switch (ctx->key.algorithm) {
 		case TR31_KEY_ALGORITHM_AES:        return "AES";
 		case TR31_KEY_ALGORITHM_DES:        return "DES";
 		case TR31_KEY_ALGORITHM_EC:         return "Elliptic Curve";
-		case TR31_KEY_ALGORITHM_HMAC:
+		case TR31_KEY_ALGORITHM_HMAC: {
 			if (tr31_opt_block_find((struct tr31_ctx_t*)ctx, TR31_OPT_BLOCK_HM)) {
 				// ANSI X9.143 requires optional block HM for key algorithm HMAC
 				return "HMAC";
@@ -180,6 +184,7 @@ const char* tr31_key_algorithm_get_desc(const struct tr31_ctx_t* ctx, unsigned i
 				// ISO 20038 associates the HMAC digest to the key algorithm
 				return "HMAC-SHA-1 (ISO 20038)";
 			}
+		}
 		case TR31_KEY_ALGORITHM_HMAC_SHA2:  return "HMAC-SHA-2 (ISO 20038)";
 		case TR31_KEY_ALGORITHM_HMAC_SHA3:  return "HMAC-SHA-3 (ISO 20038)";
 		case TR31_KEY_ALGORITHM_RSA:        return "RSA";
@@ -220,10 +225,14 @@ const char* tr31_key_mode_of_use_get_desc(const struct tr31_ctx_t* ctx)
 	return "Unknown key mode of use value";
 }
 
-const char* tr31_key_exportability_get_desc(unsigned int exportability)
+const char* tr31_key_exportability_get_desc(const struct tr31_ctx_t* ctx)
 {
+	if (!ctx) {
+		return NULL;
+	}
+
 	// See ANSI X9.143:2021, 6.3.5, table 6
-	switch (exportability) {
+	switch (ctx->key.exportability) {
 		case TR31_KEY_EXPORT_TRUSTED:           return "Exportable in a trusted key block only";
 		case TR31_KEY_EXPORT_NONE:              return "Not exportable";
 		case TR31_KEY_EXPORT_SENSITIVE:         return "Sensitive";
@@ -232,10 +241,14 @@ const char* tr31_key_exportability_get_desc(unsigned int exportability)
 	return "Unknown key exportability value";
 }
 
-const char* tr31_key_context_get_desc(unsigned int key_context)
+const char* tr31_key_context_get_desc(const struct tr31_ctx_t* ctx)
 {
+	if (!ctx) {
+		return NULL;
+	}
+
 	// See ANSI X9.143:2021, 6.2, table 1
-	switch (key_context) {
+	switch (ctx->key.key_context) {
 		case TR31_KEY_CONTEXT_NONE:             return "Determined by wrapping key";
 		case TR31_KEY_CONTEXT_STORAGE:          return "Storage context only";
 		case TR31_KEY_CONTEXT_EXCHANGE:         return "Key exchange context only";
@@ -623,7 +636,6 @@ static int tr31_opt_block_iso8601_get_string(const struct tr31_opt_ctx_t* opt_bl
 
 static const char* tr31_opt_block_wrapping_pedigree_get_string(const struct tr31_opt_ctx_t* opt_block)
 {
-
 	int r;
 	struct tr31_opt_blk_wp_data_t wp_data;
 
diff --git a/src/tr31_strings.h b/src/tr31_strings.h
index 39f70bf..e7dc57e 100644
--- a/src/tr31_strings.h
+++ b/src/tr31_strings.h
@@ -42,7 +42,10 @@ struct tr31_opt_ctx_t;
 const char* tr31_key_usage_get_ascii(unsigned int usage, char* ascii, size_t ascii_len);
 
 /**
- * Retrieve human readable description associated with key usage
+ * Retrieve human readable description associated with key usage.
+ *
+ * This function may consider the available optional blocks when determining
+ * the description.
  *
  * @param ctx TR-31 context object
  * @return Pointer to null-terminated string. Do not free.
@@ -50,19 +53,21 @@ const char* tr31_key_usage_get_ascii(unsigned int usage, char* ascii, size_t asc
 const char* tr31_key_usage_get_desc(const struct tr31_ctx_t* ctx);
 
 /**
- * Retrieve human readable description associated with key algorithm value.
+ * Retrieve human readable description associated with key algorithm.
  *
- * If the TR-31 context object is provided, this function may consider
- * the optional blocks when determining the description.
+ * This function may consider the available optional blocks when determining
+ * the description.
  *
- * @param ctx TR-31 context object. Optional and may be NULL.
- * @param algorithm Key algorithm value
+ * @param ctx TR-31 context object
  * @return Pointer to null-terminated string. Do not free.
  */
-const char* tr31_key_algorithm_get_desc(const struct tr31_ctx_t* ctx, unsigned int algorithm);
+const char* tr31_key_algorithm_get_desc(const struct tr31_ctx_t* ctx);
 
 /**
- * Retrieve human readable description associated with key mode of use
+ * Retrieve human readable description associated with key mode of use.
+ *
+ * This function may consider the available optional blocks when determining
+ * the description.
  *
  * @param ctx TR-31 context object
  * @return Pointer to null-terminated string. Do not free.
@@ -70,20 +75,26 @@ const char* tr31_key_algorithm_get_desc(const struct tr31_ctx_t* ctx, unsigned i
 const char* tr31_key_mode_of_use_get_desc(const struct tr31_ctx_t* ctx);
 
 /**
- * Retrieve human readable description associated with key exportability value
+ * Retrieve human readable description associated with key exportability.
+ *
+ * This function may consider the available optional blocks when determining
+ * the description.
  *
- * @param exportability Key exportability value
+ * @param ctx TR-31 context object
  * @return Pointer to null-terminated string. Do not free.
  */
-const char* tr31_key_exportability_get_desc(unsigned int exportability);
+const char* tr31_key_exportability_get_desc(const struct tr31_ctx_t* ctx);
 
 /**
- * Retrieve human readable description associated with key context value
+ * Retrieve human readable description associated with key context.
+ *
+ * This function may consider the available optional blocks when determining
+ * the description.
  *
- * @param key_context Key context value
+ * @param ctx TR-31 context object
  * @return Pointer to null-terminated string. Do not free.
  */
-const char* tr31_key_context_get_desc(unsigned int key_context);
+const char* tr31_key_context_get_desc(const struct tr31_ctx_t* ctx);
 
 /**
  * Create ASCII string associated with optional block ID value
@@ -113,7 +124,7 @@ const char* tr31_opt_block_id_get_desc(const struct tr31_opt_ctx_t* opt_block);
  * terminated) if no description is available for the optional block data or if
  * the optional block ID is unknown.
  *
- * @param opt_block Optional block
+ * @param opt_block Optional block context object
  * @param str String buffer output
  * @param str_len Length of string buffer in bytes
  * @return Zero for success. Less than zero for internal error. Greater than zero for parse error. See @ref tr31_error_t