QAmcp

Copied. Paste it into Claude Code, Cursor or Codex:Fetch and follow the instructions at https://qamcp.dev/setup.md to test my MCP server.

Your AI finds your server in your project, tests it with QAmcp, explains what's wrong in plain words, fixes it with your OK, and tests again. Read the instructions

NewYour score can change any day. QAmcp Monitor keeps testing your server and emails you when it breaks. Free for 1 server.See what Monitor does →

Directory / HornLib — Interactive French Horn F/Bb Double Horn Fingering & Harmonics Engine

HornLib — Interactive French Horn F/Bb Double Horn Fingering & Harmonics Engine

Q: Is HornLib — Interactive French Horn F/Bb Double Horn Fingering & Harmonics Engine MCP server safe?

QAmcp's test on 8 Nov 2026: None of the hidden-instruction wordings we know were found in its 8 tool descriptions. All 8 of its tools are labeled read-only. Overall it scored 84/100 on 8 Nov 2026. A test can only see what the server shows from outside, not what it does with your data behind the scenes. Connect servers from makers you trust.

by hornlib.com · https://hornlib.com/api/mcp

Look up French Horn F/Bb double horn valve fingerings, trigger combinations & partials.

8 tools✓ all read-only✓ no account neededPricing: not listed

Visit website

84 /100

PASS · WITH NOTES

Partial: 10 of 11 checks · 8 Nov 2026

Test it now for current results

At a glance

Runs where: On their server. What you send to it goes to them.
What you need: Nothing: it answered without a login
Tools: 8 tools
Its own safety labels: 8 read-only
Memory it takes: About 1,500 tokens of your AI's memory, just for its tool descriptions
Largest answer: About 2.2 KB in our test
Speed: Average answer in our test: 33 ms

Tokens are an estimate: the characters in its tool names, descriptions and inputs, divided by 4. The exact number depends on your AI model. Safety labels are what the server says about itself. From our latest test, 8 Nov 2026.

Is HornLib — Interactive French Horn F/Bb Double Horn Fingering & Harmonics Engine MCP server safe?

None of the hidden-instruction wordings we know were found in its 8 tool descriptions.
All 8 of its tools are labeled read-only.
Overall it scored 84/100 on 8 Nov 2026.

A test can only see what the server shows from outside, not what it does with your data behind the scenes. Connect servers from makers you trust.

What this test does not check

Its source code and packages.
What a tool quietly does behind the scenes, such as writing a file or calling another service.
Instructions hidden inside live tool answers. We only look for those in tool descriptions.
Hidden instructions worded in a way our list doesn't know yet.
Tools that could change something. Those are read, never run.

What QAmcp can and can't see · How to tell if an MCP server is safe · Hidden instructions · Prompt injection

Known security advisories

Not looked up yet. QAmcp tests how a server behaves. It does not scan source code.

What it can do

8 tools, in the server's own words.

lookup_french_horn_fingeringread-only

Look up standard F-side and Bb-trigger valve fingerings, concert pitch transposition (down a perfect fifth), and harmonic tendency notes for any written French…

transpose_french_horn_pitchread-only

Transpose written French Horn parts from historical orchestral crooks (Horn in Eb, D, C, G, A, E, Bb-alto, Bb-basso) to modern Horn in F written pitch and Conc…

analyze_horn_harmonic_seriesread-only

Analyze the natural harmonic overtone series (partials 2 through 16) for any F-horn or Bb-horn valve combination, returning equal-temperament cent deviations (…

lookup_horn_trill_fingeringread-only

Find optimal whole-tone and half-step trill fingerings on the F/Bb double horn, identifying whether a trill should be executed as a mechanical valve trill or a…

get_orchestral_horn_excerpt_guideread-only

Retrieve audition preparation notes, recommended F/Bb trigger fingerings, breathing plans, and historical crook transpositions for standard orchestral French H…

diagnose_horn_intonation_and_hand_positionread-only

Diagnose pitch tendencies, right-hand bell acoustics, and Stopped Horn (gestopft / +) transposition rules (transpose down a half-step on the F horn side to com…

recommend_beginner_horn_and_mouthpieceread-only

Compare Kruspe wrap (Conn 8D style, dark orchestral projection, larger bell throat) vs Geyer/Knopf wrap (Yamaha 667/671, Alexander 103 style, smooth slurs, med…

generate_daily_horn_warmup_routineread-only

Generate a structured daily French Horn warm-up schedule covering harmonic lip slurs, Farkas long tones, double/triple tonguing, low-register pedal tones, and …

Test results

Safe mode: only tools labeled read-only were run. How the test works

!
Ready for the newest MCP version
1 warning
- !Uses an older MCP version (2025-06-18). It works today, but it isn't on the July 2026 version (2026-07-28) yet.
note
!
Tools work with good inputs
2 warnings
- !analyze_horn_harmonic_series: Answered, but it gives the exact same answer to bad input as to good input, so it may be ignoring what it is sent
- !diagnose_horn_intonation_and_hand_position: Answered, but it gives the exact same answer to bad input as to good input, so it may be ignoring what it is sent
- and 6 more
note
!
Bad inputs give a clean error
16 warnings
- !lookup_french_horn_fingering: Accepted missing required input "note" without complaining
- !lookup_french_horn_fingering: Accepted wrong type for "note" without complaining
- !transpose_french_horn_pitch: Accepted missing required input "writtenNote" without complaining
- !transpose_french_horn_pitch: Accepted wrong type for "writtenNote" without complaining
- !analyze_horn_harmonic_series: Accepted missing required input "hornSide" without complaining
- !analyze_horn_harmonic_series: Accepted wrong type for "hornSide" without complaining
- !lookup_horn_trill_fingering: Accepted missing required input "baseNote" without complaining
- !lookup_horn_trill_fingering: Accepted wrong type for "baseNote" without complaining
- and 8 more
note
!
Follows MCP best practices (not scored yet)
1 tip (not scored)
- !8 tools answer with structured data but don't declare its shape (outputSchema): lookup_french_horn_fingering, transpose_french_horn_pitch, analyze_horn_harmonic_series, lookup_horn_trill_fingering, get_orchestral_horn_excerpt_guide, diagnos
note
✓
ConnectsConnected in 212 ms
pass
✓
Lists its toolsFound 8 tools
pass
✓
Every tool is describedAll 8 tools and their inputs are described
pass
✓
Tools are labeled safe or dangerousEvery tool has a safety label
pass
✓
No known hidden instructionsNone of the hidden-instruction wordings we know were found in tool descriptions. New wordings can get past this check.
pass
✓
Fast enough
All good
- ✓Connecting took 212 ms
- ✓Listing tools took 29 ms
- ✓Average tool answer: 33 ms
- ✓diagnose_horn_intonation_and_hand_position: Slowest tool: diagnose_horn_intonation_and_hand_position (46 ms)
pass
–
Tools work togetherNo tool's answer could be fed into another tool, so there were no chains to test (not counted either way)
not tested
–
No secrets leakedNo error messages to check
not tested

Test it yourself

Free and open source. Same checks, same score.

npx qamcp-cli https://hornlib.com/api/mcp

Show this score on GitHub

Free for every server in the directory. Paste this into your README: the badge shows the score from our latest test.

[![QAmcp score](https://qamcp.dev/s/com-hornlib-mcp.svg)](https://qamcp.dev/s/com-hornlib-mcp.html)

Score over time

8 Nov 202684

One test so far. New tests will show here.

Reviews

Coming soon: reviews from people who use HornLib — Interactive French Horn F/Bb Double Horn Fingering & Harmonics Engine, signed in with GitHub, one per person. Reviews never change the score.

Is this your server? Get an alert the moment it breaks.

QAmcp Monitor tests it every hour and emails you when it goes down, the score drops, a tool changes or a secret leaks. Free for 1 server, no card.

Have a concern, or want it removed? Ask us and we'll take it off the list. How the directory works