Eigenstyle

eigenstyle — your voice profile as a tool

A Rust workspace that turns a measured writing fingerprint (built 2026-10-11 in the matt-voice skill) into a living system: an MCP server agents can call, a terminal UI, and a GPUI desktop GUI — all over one core library, all fed by a corpus you keep adding to. [License: Apache 2.0]

The fingerprint is measured, not vibes: sentence-length distribution, function-word profile, punctuation rates, parentheticals, hyphenated compounds, hedge/assertive balance, first-person rate — the same features, tokenizer, rounding, and leave-one-out band calibration as the skill's Python reference. A parity test suite proves the Rust engine reproduces the Python numbers on the seed corpus (features and bands identical; checker deltas on the held-out pieces match: JAS 1.196, Cureus 1.088, synthetic 1.253).

The three front-ends

All three share one store: $EIGENSTYLE_HOME, else ~/.local/share/eigenstyle/. First open seeds it from the skill's corpus (6 pieces, 7,674 words), fingerprint, and readable profile.

MCP tools

Protocol: MCP over stdio on rmcp 3.8 (the official Rust MCP SDK), modern era only (protocol version 2026-07-28). Sessions open with server/discover and every request carries its protocol version in _meta — there is no initialize handshake. Legacy-era contact is refused at the stdio front door with the typed -32022 unsupported-version error. Fail-closed throughout: malformed frames, unknown tools, strict argument schemas, named size bounds everywhere.

Versions (1.0 release): the MCP server eigenstyle, the TUI, and the GUI are 1.0.0. eigenstyle-core stays at 0.1.0 — that version is already published on crates.io and does not move with this release.

Adding your writing

• MCP: an agent calls ingest_sample (or you ask for a URL fetch — the core fetches it, bounded, HTML reduced to text).
• TUI: Add writing screen (key 2) — title, genre, authorship toggle, source, then a file path (Enter loads it) or pasted text; Ctrl+S saves.
• GUI: Add writing tab — same fields as clickable boxes; the authorship button toggles sole/blended; Add sample saves.

In every flow the same rules hold: samples are append-only (exclude a sample from the fingerprint instead of deleting history), and the fingerprint never changes silently — recompute is explicit, with a dry-run preview first.

Correcting the fingerprint

The fingerprint dashboard (TUI Fingerprint screen, GUI Fingerprint tab) lists every feature's mean/SD. Select one, type a corrected mean, apply: the value is stored as a user correction overlaid on the computed reference. Corrections survive recompute, are marked wherever they show, and can be cleared wholesale to restore computed values exactly.

Patterns adapted from same-kind tools

• HumanifyMe — the editable, human-readable fingerprint, and the deterministic post-draft verify gate (dropped numbers / broken URLs in check_draft).
• brandvoice-mcp — ingest → chunk → exemplar retrieval bank (get_exemplars serves corpus paragraphs by genre).
• book-writer-mcp / Eden — per-genre style profiles (the dashboard shows pooled per-genre stats), and the builder flow where induced rules are shown for correction before they are saved (recompute dry-run preview → apply).
• Arcitext — tone-fit via an explicit avoid list, enforced by the checker and editable in the Profile view.

Bounds (named, enforced)

Sample text ≤ 256 KiB and ≥ 10 tokens; draft ≤ 1 MiB, < 200 words = UNRELIABLE verdict (integrity/avoid checks still run); URL fetch ≤ 1 MiB, 15 s, HTTP(S) only, ≤ 3 redirects; JSON-RPC line ≤ 4 MiB; fingerprint build needs ≥ 2 included pieces (leave-one-out calibration is undefined below that) and fails closed otherwise.

Platform notes

• Toolchain pinned to Rust 1.99.0 (rust-toolchain.toml), matching the estate. GPUI is pinned exactly: gpui-ce = =0.2.2 + gpui_ce_platform = =0.1.0 (features wayland, x11).
• GUI rendering is verified on Wayland (primo's desktop is Hyprland; the smoke runs under a headless wlroots compositor). Under Xvfb/X11 this GPUI build presents black frames — use a Wayland session.
• GUI text entry is click-to-focus, append/backspace only (no selection/IME yet) — a stated limit, tracked in PROGRESS.md.

Layout

crates/eigenstyle-core   corpus store, stylometry, fingerprint build, checker, fetchcrates/eigenstyle    stdio MCP server (6 tools)crates/eigenstyle-tui    ratatui TUI (eigenstyle-tui --snapshot <screen> renders headlessly)crates/eigenstyle-gui    GPUI GUIscreenshots/        smoke evidence (GUI corpus + fingerprint views, probe)

License

This project is licensed under the Apache License, Version 2.0.