# Chess Masti AI

> Free, conversational chess coaching at chessmasti.com. Stockfish 17 evaluates positions, Claude translates the verdict into language, a hallucination validator checks every claim against the live board, and adaptive puzzles come from a 100,000+ position Neo4j graph re-ranked by FEN cosine similarity.

## What it is

- Web app, Next.js 15 + TypeScript on Vercel.
- Free, no paid tier. Built and maintained by Aayan Hetamsaria, a high-school student.
- Priority markets: India, Southeast Asia.

## Engine layer (runs before the LLM, not after)

- Stockfish 17 WASM in-browser worker.
- Tactical motif detection, candidate-move gap analysis, branch-point analysis.

## LLM layer

- Anthropic Claude. Sonnet for deep analysis. Haiku for sub-5-second chat with server-side context caching.

## Validator layer

- Hallucination validator: every coaching response is parsed and each piece, square, and move reference is checked against the live chess.js board state. Failed claims are rewritten or discarded.

## Humanlike opponent

- Twin Bot is built on Maia-2 (NeurIPS 2024), deployed as a FastAPI/PyTorch microservice on Hugging Face Spaces.
- Optional opening-tree mirroring of a public Lichess player.

## Puzzle retrieval

- Neo4j Aura graph: 100,000+ quality-filtered Lichess puzzles (popularity ≥ 60, plays ≥ 50, rating deviation ≤ 120).
- 46 tactical themes × 4 difficulty bands.
- Joined with 298,000+ Jhamtani expert-commentary pairs.
- Graph traversal + 49-dimensional FEN cosine-similarity re-ranking against the user's mistake position.
- SM-2 spaced repetition over puzzle progress.

## Live play

- Lichess OAuth 2.0 PKCE.
- Dual-SSE live game stream.

## Opponent scouting

- Lichess / Chess.com username → opening trees, repertoire collisions, "Stalker Score" exploitability index, tilt and timeout psychology profiles, shareable SVG player card.

## Pages

- [How it works](https://chessmasti.com/how-it-works): the engine → LLM → validator → puzzle pipeline in plain English.
- [Architecture](https://chessmasti.com/architecture): technical deep-dive.
- [Compare](https://chessmasti.com/vs): comparison against Sensei Chess, Noctie, Chessvia, DecodeChess, Chess.com Coach.
- [FAQ](https://chessmasti.com/faq): common questions about the pipeline, validator, Maia-2, pricing.

## What we don't do

- No paid tier.
- No advertising.
- No selling game data.
- No fine-tuned proprietary chess LLM. The validator is the trust layer.