diff --git a/README.md b/README.md
index c14437e..9f4d269 100644
--- a/README.md
+++ b/README.md
@@ -123,3 +123,19 @@ Options:
 ```
 Log file of test run is written in js_tests_log.txt in the
 server/tests/js_tests/tests folder.
+
+This reference does not provide code for sleeping an app, so
+tests that involve sleeping an app will fail.
+
+There is also a test suite for lightly testing how the implementation handles edge cases.
+this can be run with:
+```
+server/tests/js_tests/tests$ node testEdgeCases.js 
+
+Usage: node testEdgeCases.js[options]
+
+Options:
+  --host      IP address of host on which DIAL server under test is running
+                                                             [string] [required]
+  --help, -h  Show help                                                [boolean]
+```
diff --git a/server/dial_data.c b/server/dial_data.c
index ac62527..45c4dcd 100644
--- a/server/dial_data.c
+++ b/server/dial_data.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Netflix, Inc.
+ * Copyright (c) 2014-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -40,6 +40,13 @@ void set_dial_data_dir(const char *data_dir) {
 
 /**
  * Returns the path where data is stored for the given app.
+ *
+ * The DIAL data directory must have been already set.
+ *
+ * @param app_name application name.
+ * @return the location of the application path within the DIAL data
+ *         directory or NULL if memory could not be allocated.
+ * @see set_dial_data_dir(const char*)
  */
 static char* getAppPath(char *app_name) {
     size_t name_size = strlen(app_name) + sizeof(dial_data_dir) + 1;
diff --git a/server/dial_data.h b/server/dial_data.h
index 55a5c7d..a075953 100644
--- a/server/dial_data.h
+++ b/server/dial_data.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Netflix, Inc.
+ * Copyright (c) 2014-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -46,6 +46,13 @@
  */
 #define DIAL_DATA_URI "/dial_data"
 
+/**
+ * The DIAL data key and value values cannot contain any spaces. They are
+ * expected to be URL-escaped strings, so any spaces would be represented as
+ * the '+' character. They have a max length of 255 characters.
+ *
+ * THE STRINGS key AND value POINT TO MUST BE DYNAMICALLY ALLOCATED
+ */
 struct DIALData_ {
     struct DIALData_ *next;
     char *key;
@@ -54,12 +61,45 @@ struct DIALData_ {
 
 typedef struct DIALData_ DIALData;
 
+#define DIAL_KEY_OR_VALUE_MAX_LEN (255)
+#define DIAL_KEY_OR_VALUE_MAX_LEN_STR "255"
+
+/**
+ * Store the DIAL data key/value pairs in the application data store.
+ *
+ * Will exit immediately if the data output file cannot be accessed due to
+ * out-of-memory or I/O errors.
+ *
+ * Keys and values are truncated to DIAL_KEY_OR_VALUE_MAX_LEN.
+ *
+ * @param app_name application name.
+ * @param data pointer to head of DIAL data linked list.
+ */
 void store_dial_data(char *app_name, DIALData *data);
 
+/**
+ * Retrieve the DIAL data key/value pairs from the application data store.
+ *
+ * @param app_name application name.
+ * @return data pointer to head of DIAL data linked list or NULL if
+ *         there is no valid data or if the data output file cannot be accessed
+ *         due to out-of-memory or I/O errors.
+ */
 DIALData *retrieve_dial_data(char *app_name);
 
+/**
+ * Set the DIAL data directory.
+ *
+ * @param data_dir the DIAL data directory path, which must include the
+ *        trailing directory separator (e.g. '/' character).
+ */
 void set_dial_data_dir(const char *data_dir);
 
+/**
+ * Frees the DIAL data linked list memory.
+ *
+ * @param dialData pointer to the DIAL data linked list.
+ */
 void free_dial_data(DIALData **dialData);
 
 #endif /* SRC_SERVER_DIAL_DATA_H_ */
diff --git a/server/dial_server.c b/server/dial_server.c
index 16d62e6..48c0ddf 100644
--- a/server/dial_server.c
+++ b/server/dial_server.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Netflix, Inc.
+ * Copyright (c) 2014-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -94,8 +94,14 @@ static int ds_unlock(DIALServer *ds) {
     return 1;
 }
 
-// finds an app and returns a pointer to the previous element's next pointer
-// if not found, return a pointer to the last element's next pointer
+/**
+ * Finds an application in the DIAL server application linked list.
+ *
+ * @param ds the DIAL server.
+ * @param app_name application name.
+ * @return a pointer to the DIAL application; the pointer value may be NULL if
+ *         the application was not found.
+ */
 static DIALApp **find_app(DIALServer *ds, const char *app_name) {
     DIALApp *app;
     DIALApp **ret = &ds->apps;
@@ -129,9 +135,13 @@ static int url_decode_xml_encode(char *dst, char *src, size_t src_size) {
     return 1;
 }
 
-/*
- * A bad payload is defined to be an unprintable character or a
- * non-ascii character.
+/**
+ * Checks if a payload string contains invalid characters.
+ *
+ * @param pPayload payload string.
+ * @param numBytes length of payload string in bytes (excluding trailing NULL).
+ *
+ * @return 1 if the payload contains an unprintable or non-ASCII character.
  */
 static int isBadPayload(const char* pPayload, int numBytes) {
     int i = 0;
diff --git a/server/dial_server.h b/server/dial_server.h
index c9b0c7a..5913a08 100644
--- a/server/dial_server.h
+++ b/server/dial_server.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Netflix, Inc.
+ * Copyright (c) 2014-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -59,7 +59,9 @@ typedef enum {
 #define DIAL_MAX_PAYLOAD (4096)
 
 /*
- * The maximum additionalDataUrl length
+ * The maximum additionalDataUrl length.
+ *
+ * There is no value defined in the DIAL specification.
  */
 
 #define DIAL_MAX_ADDITIONALURL (1024)
@@ -120,6 +122,8 @@ DIALServer *DIAL_create();
  * Starts the DIAL server.
  *
  * @param[in] ds DIAL server handle
+ * @return true if the DIAL server was started and the DIAL server handle
+ *         now contains a valid Mongoose context.
  */
 int DIAL_start(DIALServer *ds);
 
@@ -141,7 +145,7 @@ void DIAL_stop(DIALServer *ds);
  * @param[in] if non-0, the app supports DIALadditionalDataURL.
  * @param[in] if non-NULL, specifies the CORS allowed origin for this app.
  *
- * @return 1 if successful, 0 otherwise
+ * @return 1 if successful, 0 if already registered, -1 on error.
  */
 int DIAL_register_app(DIALServer *ds, const char *app_name,
                       struct DIALAppCallbacks *callbacks,
@@ -154,7 +158,7 @@ int DIAL_register_app(DIALServer *ds, const char *app_name,
  * @param[in] ds DIAL server handle
  * @param[in] app_name Name of the DIAL application
  *
- * @return 1 if successful, 0 otherwise
+ * @return 1 if successful, 0 if not found, -1 on error.
  */
 int DIAL_unregister_app(DIALServer *ds, const char *app_name);
 
diff --git a/server/mongoose.c b/server/mongoose.c
index 97f3af3..0edacc5 100644
--- a/server/mongoose.c
+++ b/server/mongoose.c
@@ -304,6 +304,14 @@ void mg_send_http_error(struct mg_connection *conn, int status,
   conn->num_bytes_sent += mg_printf(conn, "%s", buf);
 }
 
+/**
+ * Create a new thread.
+ *
+ * @param ctx Mongoose context.
+ * @param func thread function.
+ * @param param thread function arguments.
+ * @return the return value of pthread_create.
+ */
 static int start_thread(struct mg_context *ctx, mg_thread_func_t func,
                         void *param) {
   pthread_t thread_id;
diff --git a/server/nf_callbacks.c b/server/nf_callbacks.c
index ae414c9..01c9a11 100644
--- a/server/nf_callbacks.c
+++ b/server/nf_callbacks.c
@@ -1,3 +1,27 @@
+/*
+ * Copyright (c) 2014-2019 Netflix, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY NETFLIX, INC. AND CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL NETFLIX OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
diff --git a/server/nf_callbacks.h b/server/nf_callbacks.h
index 95b0648..a9626ee 100644
--- a/server/nf_callbacks.h
+++ b/server/nf_callbacks.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Netflix, Inc.
+ * Copyright (c) 2014-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
diff --git a/server/system_callbacks.c b/server/system_callbacks.c
index 9a2d14f..bc3555e 100644
--- a/server/system_callbacks.c
+++ b/server/system_callbacks.c
@@ -1,3 +1,27 @@
+/*
+ * Copyright (c) 2018-2019 Netflix, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY NETFLIX, INC. AND CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL NETFLIX OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
 #include <string.h>
 #include <stdio.h>
 #include "system_callbacks.h"
diff --git a/server/system_callbacks.h b/server/system_callbacks.h
index db3f369..3e585a3 100644
--- a/server/system_callbacks.h
+++ b/server/system_callbacks.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 Netflix, Inc.
+ * Copyright (c) 2018-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -28,6 +28,11 @@
 
 #include "dial_server.h"
 
+/**
+ *
+ *
+ * Sleep is the only supported action for 'system', and not implemented in this reference.
+ */
 DIALStatus system_start(DIALServer *ds, const char *appname,
                             const char *payload, const char* query_string,
                             const char *additionalDataUrl,
diff --git a/server/tests/test_dial_data.c b/server/tests/test_dial_data.c
index bb6efd5..4fe6433 100644
--- a/server/tests/test_dial_data.c
+++ b/server/tests/test_dial_data.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Netflix, Inc.
+ * Copyright (c) 2014-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
diff --git a/server/url_lib.c b/server/url_lib.c
index 99d1d13..0dfa449 100644
--- a/server/url_lib.c
+++ b/server/url_lib.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Netflix, Inc.
+ * Copyright (c) 2014-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -43,6 +43,16 @@ char* smartstrncpy(char* dest, char* src, size_t max_chars) {
     return dest;
 }
 
+/**
+ * Convert a two-character hex representation into its ASCII equivalent
+ * and copy it into dest.
+ *
+ * @param dest the destination character buffer.
+ * @param a the first hex character.
+ * @param b the second hex character.
+ * @return 1 if the character was converted and copied, 0 if the hex
+ *         characters are invalid.
+ */
 static int append_char_from_hex(char* dest, char a, char b) {
     if ('a' <= a && a <= 'f')
         a = 10 + a - 'a';
diff --git a/server/url_lib.h b/server/url_lib.h
index 537a790..d3fb30b 100644
--- a/server/url_lib.h
+++ b/server/url_lib.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Netflix, Inc.
+ * Copyright (c) 2014-2019 Netflix, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -31,35 +31,94 @@
 #include <stddef.h>
 
 /**
- * Concatenate a maxim of max_chars characters from src into dest,
- * and return a pointer to the last character in dest.
+ * Copy a maximum of max_chars characters from src into dest,
+ * and return a pointer to the terminating NULL in dest.
+ *
+ * @param dest destination buffer.
+ * @param src string written into the destination buffer
+ * @param max_chars maximum number of characters to put into the destination
+ *        buffer, excluding the trailing NULL. Must be less than or equal to
+ *        the number of bytes available at dest - 1.
+ * @return a pointer to the end of the written string (the location of the
+ *         terminating NULL).
  */
 char* smartstrncpy(char* dest, char* src, size_t max_chars);
 
+/**
+ * URL-unescape the source string into the destination string, up to the
+ * maximum number of destination characters.
+ *
+ * @param dst raw string buffer.
+ * @param src URL-escaped source string.
+ * @param max_size maximum number of characters to put into the destination
+ *        buffer, excluding the trailing NULL. Must be less than or equal to
+ *        sizeof(dst) - 1.
+ * @return the length of the raw string excluding the trailing NULL. Will be
+ *         0 if there were no characters to unescape or if the source string
+ *         was malformed.
+ */
 int urldecode(char *dst, const char *src, size_t max_size);
 
+/**
+ * XML-escape the source string into the destination string, up to the maximum
+ * number of destination characters.
+ *
+ * @param dst XML-escaped string buffer.
+ * @param src raw source string.
+ * @param max_size maximum number of characters to put into the destination
+ *        buffer, excluding the trailing NULL. Must be less than or equal to
+ *        sizeof(dst) - 1.
+ * @return the length of the XML-escaped string excluding the trailing NULL.
+ */
 void xmlencode(char *dst, const char *src, size_t max_size);
 
 /**
- * Parse the value of the parameter with the given name from a query string.
+ * Return the value in the query string for the requested parameter name.
+ *
+ * @param query_string the URL query string.
+ * @param param_name the parameter name.
+ * @return the parameter value or NULL if out-of-memory. The caller must free
+ *         the returned memory.
  */
 char *parse_param(char *query_string, char *param_name);
 
-/*
- * Parse the application name out of a URI, such as /app/YouTube/dial_data.
- * Note: this parser assumes that the dial_data url is of the form
- * /apps/<app_name>/dial_data. If your DIAL server uses a different url-path,
- * you will need to adapt the method below.
+/**
+ * Parse the application name out of the full URI, for example
+ * /app/YouTube/dial_data. The application name identified as the string
+ * appearing before the last trailing slash, possibly prefixed with a slash,
+ * so /apps/<app_name>/dial_data and YouTube would be the application name in
+ * the previous example.
+ *
+ * If your DIAL server uses a different path format you will need to change
+ * this method to match.
+ *
+ * @param uri the URI, there must be a trailing slash.
+ * @return the application name, or "unknown" if two slashes cannot be found
+ *         or the application name is zero-length, or NULL if out-of-memory.
+ *         The caller must free the returned memory.
  */
 char *parse_app_name(const char *uri);
 
-/*
- * Parse a list of DIALData params out of a query string.
+/**
+ * Return a linked list of DIAL data constructed from the name/value parameter
+ * pairs of the provided query string.
+ *
+ * This function must be called while holding a mutex and is not itself
+ * thread-safe.
+ *
+ * @param query_string the URL query string.
+ * @return the DIAL data or NULL if there is none (e.g. parse error) or out-of-
+ *         memory. The caller must free the returned memory.
  */
 DIALData *parse_params(char * query_string);
 
-/* Returns a url-encoded version of str */
-/* IMPORTANT: be sure to free() the returned string after use */
+/**
+ * Return the URL-escaped version of the provided string, which may be as
+ * large as 3x the size of the provided string, plus a trailing NULL byte.
+ *
+ * @return the URL-escaped version of the provided string. The caller must
+ *         free the returned string.
+ */
 char *url_encode(const char *str);
 
 #endif  // URLLIB_H_