laya-mcp (PerryLink): a warm sidecar that fixes Laya's silent truncation and constant noul

# laya-mcp

[Laya](https://github.com/NandhaKishorM/laya) is a fast, non-autoregressive
"System 1" decision model: it answers typed questions — `noul` (yes/no),
`choice`, `score` — over a piece of state and returns probabilities, in a single
forward pass. It is genuinely good, and it is a research artifact.

This is the part that makes it survive contact with a server.

[English](README.md) · [简体中文](README-zh.md) · [Español](README-es.md) · [Português](README-pt.md) · [हिन्दी](README-hi.md)

```bash
pip install 'laya-mcp[mcp]'
laya-mcp serve            # loads the model once, keeps it warm on 127.0.0.1:8787
laya-mcp install          # registers it with whichever agent harness you have
```

> **Status: 0.2.1, work in progress.** The core is implemented and its pure logic
> is covered by 85 checks, but it has not yet been exercised end-to-end against a
> live harness in CI. Interfaces may move before 1.0.

---

## The problem this solves

Laya truncates things silently, and the omissions are the kind you only notice
after acting on a wrong answer.

**It cuts the state, from the end, and says nothing.** `build_sequence` gives the
state whatever room is left after the options and slices it `st[:room]`. A long
document loses its tail — which for a contract, a log or an email thread is often
where the answer was — and the model then answers about the surviving prefix at
full confidence. Nothing in the response marks it.

**It shortens options until labels are indistinguishable.** Options share a fixed
`head_max_len` budget (192 tokens on the English checkpoint, 256 on the others).
Past a point every label gets ~4 tokens. This is the documented cause of the
Banking77 collapse (0.425 against Jev's 0.870), and again, nothing reports it.

**Its validation is one check.** An unkno