hornlib

HornLib — Interactive French Horn F/Bb Double Horn Fingering & Harmonics Engine (com.hornlib/mcp)

Digital French horn fingering charts and transposed brass sheet music.
HornLib (hornlib.com) provides interactive fingering charts for single F, single Bb, and full double horns (F/Bb trigger), natural overtone harmonic series tables, historical orchestral crook transposition, and orchestral audition excerpt guides — exposed to AI agents via a stateless streamable-http Model Context Protocol (MCP) server at https://hornlib.com/api/mcp.

🖥️ Interactive Web Studio Preview

Why Hornists & Brass Pedagogues Choose HornLib

1. Interactive Double Horn Trigger Toggle: Dynamically switches between single F horn, single Bb horn, and full double horn (F/Bb trigger) valve combinations across the instrument's four-octave compass (C1–F6).
2. Harmonic Partial Intonation Deviation Charts: Displays exact equal-temperament cent tendencies (e.g., -14 cents on the 5th partial, -31 cents on the 7th partial, -49 cents on the 11th partial) alongside alternate valve solutions.
3. Historical Orchestral Crook Transposition: Assists hornists reading classical and romantic orchestral parts in Horn in F, Bb-alto, Bb-basso, Eb, D, C-basso, G, A, and E.

🛠️ 8 Read-Only MCP Tools (https://hornlib.com/api/mcp)

All 8 tools are strictly read-only (readOnlyHint: true, destructiveHint: false, idempotentHint: true) and require no sign-in and no API keys:

| # | Tool Name | Capability & Music Theory Scope | Web Reference |
| :-: | :--- | :--- | :--- |
| 1 | lookup_french_horn_fingering | Look up F-side & Bb-trigger valve fingerings, concert pitch transposition, and intonation tendencies for any written note (C1–F6). | Fingering Chart |
| 2 | transpose_french_horn_pitch | Transpose orchestral horn parts from historical crooks (F, Bb, Eb, D, C, G, A, E) to modern Horn in F & Concert Pitch. | 7-in-1 Brass Tools |
| 3 | analyze_horn_harmonic_series | Analyze natural overtone partials (1st–16th) for any F or Bb valve combination with cent deviations and tube lengths. | All Notes & Harmonics |
| 4 | lookup_horn_trill_fingering | Identify mechanical valve trills vs Viennese harmonic lip trills for whole-step and half-step ornaments. | Trill Fingerings |
| 5 | get_orchestral_horn_excerpt_guide | Audition preparation notes, crook shifts & fingerings for Mozart 4, Strauss Till Eulenspiegel, Tchaikovsky 5, Brahms & Mahler. | Orchestral Excerpts |
| 6 | diagnose_horn_intonation_and_hand_position | Acoustic diagnostic for Stopped Horn (gestopft +1/2 step F-horn transposition) & right-hand bell cupping. | Pedagogy Guides |
| 7 | recommend_beginner_horn_and_mouthpiece | Compare Kruspe wrap (Conn 8D) vs Geyer wrap (Alexander 103 / Yamaha) & mouthpiece cup depths (Farkas, Laskey, Schilke). | Beginner Guide |
| 8 | generate_daily_horn_warmup_routine | Generate structured daily warm-up routines covering Farkas long tones, harmonic lip slurs, tonguing & pedal tones. | Knowledge Base |

⚡ Install in Hermes Agent

This repository is a configuration-only Agent Plugins v1 package (plugin.json, mcp.json, and skills/) for Hermes Agent.

hermes plugins install hornlib

Or install directly from GitHub:

hermes plugins install HornLib/mcp-server

Example Prompts in Hermes

• "Look up the primary and alternate F/Bb double horn valve fingerings for written high A5."
• "Transpose written G4 on Horn in Eb to modern Horn in F and concert pitch."
• "Compare the harmonic series partials and cent deviations for open F horn vs open Bb horn."
• "Give me the horn key, tempo, and practice tips for Strauss's Till Eulenspiegel opening horn call."

⚡ Quick Setup (Claude Desktop / Claude Code / Cursor / Windsurf / Skills CLI)

Install Agent Skill (skills.sh)

npx skills add HornLib/mcp-server

Direct Remote streamable-http Connection

{
  "mcpServers": {
    "hornlib": {
      "type": "streamable-http",
      "url": "https://hornlib.com/api/mcp"
    }
  }
}

Claude Code CLI

claude mcp add --transport http hornlib https://hornlib.com/api/mcp

🔒 Security & Data Disclosure (Hermes Catalog Rule 13)

• Hosted-only, configuration-only package: This repository ships only static JSON manifests (plugin.json, mcp.json) and Markdown skills (skills/). It contains no local executable code, no Python runtime, no shell hooks, no compiled binaries, no telemetry collectors, and no self-updater.
• Network: Every MCP tool call connects over HTTPS (streamable-http) to HornLib's hosted endpoint at https://hornlib.com/api/mcp and sends only the musical query arguments (such as note name, horn key, or excerpt name). The remote tool inventory is served at runtime by hornlib.com and is not frozen by the pinned commit SHA.
• No credentials or sign-in: All 8 tools are public and free. No API keys, OAuth tokens, environment variables, or local files are read or stored.
• Read-only & untrusted gate: Every tool on https://hornlib.com/api/mcp is strictly read-only (readOnlyHint: true, destructiveHint: false). The package marks the server trust: untrusted in plugin.json (extensions.com.nousresearch.hermes.servers.hornlib.trust = "untrusted"), so Hermes enforces its approval gate if any non-read-only tool were ever advertised.
• Privacy & Terms: Privacy Policy · Terms of Use

🔗 Official Resources & Deep Links

• French Horn Fingering Chart (Interactive Studio)
• Double Horn F/Bb Trigger Fingering Reference
• 7-in-1 French Horn Transposition & Practice Suite
• Orchestral French Horn Audition Excerpts
• French Horn Beginner Guide & Mouthpiece Selector
• LLMs.txt Structured AI Reference

Educational music resource curated by brass pedagogues. MIT License © HornLib (hornlib.com).

README from the reviewed commit 50d9ea4; it updates when the author re-pins.