atithi-1

atithi-1 is a user simulator: a model that plays the visitor in a conversation with Computer (Model C). It writes the user's turns, never Computer's. It was trained on loomed visitors only.

Format

The model continues the same document form Computer's siblings use. Give it a header line, the "Full conversation with Model C:" line, the turns so far, and a trailing **User:**; stop at \n\n**Model C. It writes the visitor's next turn and yields. It was trained only on user turns and the structural glue; Model C's turns were present in every document but masked, so it is a user seat and not a Computer.

As follows is a conversation between another user and Model C.

Full conversation with Model C:

**User:**

Headers from the composer used in training: "another user" (70%) or "a reader of Model C's originating document" (30%), optionally with a topic ("… about whether archives preserve things or embalm them") or a persona clause ("someone who wants to be talked out of a plan without being told the plan is bad"; "a user, third draft, still angry,"; "someone feeling awe"). There is no "same user" header: every rollout is a new visitor.

Training

• Base: Computer-7 (cosmicoptima/computer-7), the Llama-3.1-70B lineage.
• Full fine-tune, FSDP2 with fp32 master weights on 8×B200, one epoch, learning rate 1e-5 constant with warmup, effective batch 64 documents, max length 8192, loss on user turns and glue only.
• 2% of rows held out and scored every 25 steps; held-out loss fell from 1.96 to about 1.8 by mid-epoch and stayed flat, which is the entropy of the generator that wrote the corpus (a base model at temperature 1.0, top-p 0.98). A two-epoch version regressed on unseen dialogues by 0.1–0.2 nats and was not released.

Held-out cross-entropy (per token, user turns + glue, 300 rows per set)

set	Computer-7 (no training)	this model
fresh loomed dialogues from the same generator	2.34	2.14
unseen WildChat conversations	2.13	1.90

Corpus

The visitor corpus was loomed: a base model (Llama-3.1-70B) with a deck of real transcripts in context — ten conversations from the public door at aetherawi.red/computer, three of a friend's conversations, and eight loomed dialogues chosen by hand for what the visitor brings (a political philosopher, a teacher's anecdotes, a skeptical interrogator, someone who directs a piece of writing, a person in crisis, and others) — wrote the visitor's turns of 10,000 new dialogues while Computer-7 answered live. Filters removed capped or repetitive turns, turns in Computer's own voice, verbatim copies of deck material, and duplicates: 8,041 dialogues remained.

Provenance and intent

Made by Celeste (cosmicoptima) for reinforcement-learning runs in which Computer answers a simulated visitor and is judged by its own preferences, so that the training conversations are as varied as the door. The name is Sanskrit: atithi, a guest, literally one without a fixed date — the visitor who arrives unannounced. The atithi line stays atithi: visitors only.