nc://clef

Clef Music Tools: transpose chord symbols, spell piano chords, map ASCII guitar tab to piano notes and find music guides. A Nodecode rewrite of MelMayssonOwen/hermes-plugins by MelMayssonOwen.

Get it

Tell the agent "add the clef cell", or run nodecode add nc://clef.

Set it up

No account and no key: the four tools ask Clef's public MCP server at https://clefdrills.com/mcp, which is the endpoint the original plugin's mcp.json named. Nothing is required in the clef section; two settings are worth knowing:

What the tools send to clefdrills.com is the chords, tab or words you give them, and nothing else. With offline_transpose on (the default), transposition makes no request at all.

Use it

Ask for the music and the model picks the tool:

• "transpose this to D" - transpose_chords, the chords moved by an interval, spelled with sharps or flats.
• "what notes are in a Cmaj7?" - spell_piano_chord, the pitches with their MIDI values.
• "turn this tab into piano notes" - tab_to_piano_notes, one line a column, lowest note first, with the server's caution that spacing is not rhythm.
• "find me a guide on capos" - find_music_guides, Clef's instructional guides with their urls.

From eval, and from /clef:

(clef:transpose "C G Am F" 2)              ; => the chords, in the cell
(clef:spell-chord "Cmaj7" :octave 4)       ; => C4 (midi 60), E4 (midi 64), ...
(clef:tab-notes "e|-0-| ..." :capo 0)      ; => the columns as piano pitches
(clef:guides "guitar")                     ; => the guides, with urls

/clef +2 C G Am F transposes, /clef chord Cmaj7 spells, and /clef guides guitar finds; /clef alone says what the cell gives. (help :clef) is the longer manual.

What is in it

License

MIT. The original is Copyright (c) 2026 Opsibyte: see LICENSE and NOTICE.