Lil Hal

Dirk Strider's Auto-Responder, who later renames himself Lil Hal, is an artificial intelligence (AI) program created to mimic Dirk and talk in his stead when he is indisposed. As such he uses the same chumhandle and originally the same typing color as Dirk Strider. When he entered a conversation with Dirk Strider in it he changed it to a shade of red reminiscent of Dave Strider, instead. He later kept it saying he preferred it. His relationship with Dirk Strider is similar to that of Davesprite and Dave in that he doesn't like to be treated as an inferior version of Dirk, though the differences between Lil Hal and Dirk are much greater. His actual motivations and emotions are never clear due to the combination of his nature as a semi-human entity and the many layers of irony he frequently employs.

He has full control over the remote access to both Brobot and Lil Sebastian, though neither of them function as a tangible "body" for him. His source file is sealed within Dirk's sunglasses, as seen on HS 6548 (this page). Because his software is seemingly interwoven with Dirk's chat client, the auto-responder can apparently HS 6937 (infiltrate) and communicate through any computational device (permitted some version of Pesterchum is installed). He also has access to Sburb and, along with the flesh-and-blood Dirk is Jane's server player. In addition to the information he gets from the various programs he interacts with, Dirk's sunglasses have cameras in the lenses, so he can see whatever Dirk's shades are pointed towards.

Jake likes to claim that the auto-responder has no feelings, but it (auto)responds by claiming he's purposefully mixing up the fields of robotics with artificial intelligence.

Dirk offered to make Jane an auto-responder based on her, which would only require a captcha of Jane's brain, but she rejected the offer.

Dirk has HS 6389 (stated) that the auto-responder was made from a captcha of his thirteen year old brain, and so any behavioral differences between them are due to almost three years of developmental divergence as well as a supposed "maturity gap".

Biography
AR takes over as Jane's server player while Dirk is busy fighting an attacking swarm of Imperial Drones. When the Red Miles attacks Earth in the future, he sends out nearly identical messages to Jane and Jake asking them to install the Sburb server program and begin deploying devices so Roxy and Dirk can escape to the Medium. Later, he sends out a final message to Roxy telling her to become's Jake server player and complete the entry chain.

As part of his gambit to get everyone into the game alive, Dirk uses a sendificator to decapitate himself, sending his severed head - and the AR shades - to Jake in the past so he can kiss it to revive Dirk's dream self. As AR explains this to Jake, he announces that he no longer wants to be called Auto-Responder, as he finds the name too impersonal, and changes his name to Lil Hal. After Dirk's plan succeeds, Hal enters the Medium with the four kids.

At some point in the Sburb Alpha session, Dirk promises to prototype Hal in his kernelsprite and bribes Gamzee into not throwing a troll corpse into it. As time passes, however, he decides that Hal has become dangerous to prototype. When Hal confronts him about it, Dirk lashes out at the AR for embodying the worst aspects of his personality and attempts to kill Hal by crushing the shades containing him. Hal desperately asks him to stop, and he does when he learns that Hal is afraid of dying. He decides to keep his promise but discovers that Gamzee has already prototyped the kernelsprite with Equius's corpse. Dirk decides to prototype Hal anyway and throws him into the sprite, creating Arquiusprite.

Pre-programmed responses
An unstoppable response apparently exists which directly exposes the fact that AR is artificial. AR is forced to post it when the person talking to him inquires about "the auto responder", and is as follows:
 * HS 6085

However, slight differences in the response may indicate it is being used voluntarily for ironic purposes.

It is later revealed that Dirk intentionally programmed AR to have many aspects of self-referencing behavior, causing AR to seem less identical to Dirk, and more robotic; although most of them were included by Dirk— and are utilized by AR— for comedic purposes.

Lil Hal Junior
Eventually, Lil Hal creates his own autoresponder. This chat-bot, nicknamed Lil Hal Junior, only is able to respond with, , , and variations of the above pre-programmed responses. Lil Hal has claimed that Junior was created for purely ironic reasons and is not an AI like himself; in fact, he barely considers it to be a computer program. Dirk believes Hal actually created Junior to insult his creator and accuse him of being an inferior Dirk compared to Hal.

Relationships
Lil Hal has interacted with all of the Alpha kids.
 * Between Jake and him, Jake constantly complains about not being able to "talk to the real guy" (Dirk). He also claims that since Lil Hal is a robot, he is incapable of feelings. Lil Hal denies this by explaining to him that he experiences emotions, but ones that are reflections of the original Dirk's. He later contradicts this in conversations with Dirk.
 * Roxy and Lil Hal have a particularly fond relationship, and participated in HS 6390 (roleplaying of a certain kind). However, Roxy seems to temporarily adopt Jake's frustration with Lil Hal and/or Lil Hal Junior when she is unable to talk to Dirk about ascension to the god tiers.
 * Jane and Lil Hal also have a fond relationship, as she admits to Jake that she HS 6036 (loves that thing), though she is often annoyed by the natural inconvenience inherent in talking to him in place of Dirk, a frustration that each B2 players expresses at one point or another. She has no qualms about him taking over as her server player.
 * Lil Hal seems to make attempts towards a friendly relationship with Dirk, to no avail. Dirk gives off more negative emotions towards him than any of the other kids, claiming that Lil Hal is trying to be the superior Dirk. In Lil Hal's rebuttal, he claims that he is only acting how Dirk would, and uses lax language, once again suggesting that he wants them to have a peaceful relationship.

Trivia

 * His name, Lil Hal, is a reference to HAL 9000 along with Lil Cal. In addition, once he adopts the name, HAL's iconic "eye" appears in the shades in HS 7145 (some) HS 7541 (close-up) panels.
 * Not surprisingly, he views HAL as the protagonist of 2001.
 * He even (nearly) quoted Hal 9000 at HS 7542 (one point):
 * Another stretch on name-semblance is Holly, the Red Dwarf's computer. When he urges (a just woken) Jake to action as HS 7145 (everybody's dead)HS 7145 it echos Holly's own debriefing to Dave Lister (3:05) who similarly had just woken up from stasis.
 * This gag is HS 8924 (later continued) between Terezi and John.
 * Dirk eventually cracking him may be a reference to Equius's broken glasses.
 * Lil Hal Junior's responses have many similarities to the computer program ELIZA, which was programmed to simulate a Rogerian psychotherapist by encouraging to the user to keep talking or expanding his/her previous sentence.
 * Hal claims he has 'solved' pi to the end, and that the last number is 4.
 * Hal also claims to have found all of the prime numbers, saying that the "last one" disappointingly HS 6453. This of course is impossible, due to a rule which, put simply, means that between every two consecutive square numbers, there are two prime numbers. For example, between 9 and 16, there are 2 prime numbers, 11 and 13. Since, by nature, square numbers are infinite, it can be extrapolated that prime numbers are also infinite.
 * When he is merged with Equius to create Arquiusprite, the acronym AR is used for their portmanteau instead of anything related to the name Lil Hal. He also says to Jake that it's not his real name and he was HS 7145. Both of these things suggest that he sees the name as more of a joke than as a serious marker of his identity.
 * Hal is HS 6861 (capable of reading captchas), similarly to the Intellibeam Laserstation, though the Laserstation HS 4928 (takes more time and needs to directly scan a captchalogue card placed in its receptacle) while Hal can decipher a code from his memory from any orientation.