# MusicXML Comparer (pypi · comparer-mcp)

Music-aware, multi-level comparison of two MusicXML files

- Trust score: 82/100 (high trust)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-01

## Components

- pypi · `comparer-mcp`: 82/100 (this document), [markdown](https://verifymcp.io/servers/raulkivi-comparer-mcp/comparer-mcp.md), [page](https://verifymcp.io/servers/raulkivi-comparer-mcp/comparer-mcp)

## Channel facts

- Registry: `pypi`
- Package: `comparer-mcp`
- Version: `0.2.1`
- Transport: `stdio`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-10-01.

- **Supply Chain Security**: 100/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - Runs hatchling.build at install time, a recognised build step with no custom scripting around it.
  - 3 of 50 dependencies flagged as unhealthy.
- **Provenance & Transparency**: 100/100
  - Source repository is publicly reachable at the declared URL.
  - Cryptographically verified build provenance (signed, bound to raulkivi/sheet-music-mcp).
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 4 days ago).
  - Publishes a security disclosure policy (SECURITY.md).
- **Schema Quality & AI Usability**: 77/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 905 tokens (~113/item across 8 items; 8 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 0/100
  - Stability not yet verified: not enough scan history yet (needs a 30-day window).
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 8 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 8 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a current MCP spec version (2026-07-28).

**Unverified: 1 category.** A category scored 0 because we could not verify it: a data source with nothing on this package, evidence we could not reach, or a check we could not run. We only credit what we can confirm.

## Install

### How do I install the MusicXML Comparer MCP server?

MusicXML Comparer runs locally as a PyPI package, launched with uvx comparer-mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add raulkivi-comparer-mcp -- uvx comparer-mcp
```

### Cursor

```json
{
  "mcpServers": {
    "raulkivi-comparer-mcp": {
      "command": "uvx",
      "args": [
        "comparer-mcp"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "raulkivi-comparer-mcp": {
      "command": "uvx",
      "args": [
        "comparer-mcp"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add raulkivi-comparer-mcp -- uvx comparer-mcp
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "raulkivi-comparer-mcp": {
      "type": "local",
      "command": [
        "uvx",
        "comparer-mcp"
      ],
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add raulkivi-comparer-mcp --command uvx --arg comparer-mcp
```

### Hermes

```yaml
mcp_servers:
  raulkivi-comparer-mcp:
    command: "uvx"
    args: ["comparer-mcp"]
```

### Netclaw

```json
{
  "McpServers": {
    "raulkivi-comparer-mcp": {
      "Transport": "stdio",
      "Command": "uvx",
      "Arguments": [
        "comparer-mcp"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add raulkivi-comparer-mcp -t stdio -c uvx -a comparer-mcp
```

### Other

```json
{
  "mcpServers": {
    "raulkivi-comparer-mcp": {
      "command": "uvx",
      "args": [
        "comparer-mcp"
      ]
    }
  }
}
```

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-09-28 (score 82, +11)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-09-26 (score 71)

First indexed and scored.

## MCP tools (8)

### `compare_musicxml` (~132 tokens)

Full music-aware diff of two MusicXML strings. Returns a structured ComparisonResult with global similarity score, summary statistics, and per-part/measure/note detail.

Input parameters:

- `options` (object): Comparison options (docs/architecture.md §8). expand_repeats defaults to false (opt-in — see docs/PLAN.md 'Changed decisions'); normalize_pitch, ignore_articulations, part_filter, measure_range all d…
- `reference_xml` (string, required): Reference MusicXML document as a string
- `target_xml` (string, required): Target MusicXML document as a string, compared against the reference

### `compare_musicxml_files` (~142 tokens)

Full music-aware diff of two MusicXML files on disk (.musicxml, .xml, or compressed .mxl). Returns the same structured ComparisonResult as compare_musicxml.

Input parameters:

- `options` (object): Comparison options (docs/architecture.md §8). expand_repeats defaults to false (opt-in — see docs/PLAN.md 'Changed decisions'); normalize_pitch, ignore_articulations, part_filter, measure_range all d…
- `reference_path` (string, required): Path to the reference MusicXML/.mxl file
- `target_path` (string, required): Path to the target MusicXML/.mxl file, compared against the reference

### `quick_similarity` (~74 tokens)

Fast similarity check between two MusicXML strings: returns only the 0.0-1.0 similarity score and summary statistics, without per-note detail.

Input parameters:

- `reference_xml` (string, required): Reference MusicXML document as a string
- `target_xml` (string, required): Target MusicXML document as a string, compared against the reference

### `list_changes` (~137 tokens)

List only the note-level differences (operation != MATCH) between two MusicXML strings, optionally filtered to one part and/or a measure range. Useful for targeted queries like 'what changed in the Alto, measures 17-24?'

Input parameters:

- `measure_range` (array): [start, end] measure numbers, inclusive. Omit for all measures.
- `part` (string): Restrict results to this part name (case-insensitive). Omit for all parts.
- `reference_xml` (string, required): Reference MusicXML document as a string
- `target_xml` (string, required): Target MusicXML document as a string, compared against the reference

### `generate_comparison_report` (~155 tokens)

Human-readable version comparison report: overall similarity headline, missing/extra parts, missing/extra measures, key/time signature changes, and note-level differences grouped into measure-range summaries (e.g. 'transposed by 3 semitones in measures 17-24').

Input parameters:

- `options` (object): Comparison options (docs/architecture.md §8). expand_repeats defaults to false (opt-in — see docs/PLAN.md 'Changed decisions'); normalize_pitch, ignore_articulations, part_filter, measure_range all d…
- `reference_xml` (string, required): Reference MusicXML document as a string
- `target_xml` (string, required): Target MusicXML document as a string, compared against the reference

### `export_annotated_musicxml` (~195 tokens)

Export both scores as MusicXML with per-note color annotations marking the diff (pitch changes, duration changes, substitutions, insertions, deletions). Returns two documents: reference_annotated_musicxml (shows deletions and pre-change values) and target_annotated_musicxml (shows insertions and post-change values). Feed either directly into render-mcp's render_to_pdf or render_to_image to visualize the diff — both take a raw musicxml string.

Input parameters:

- `options` (object): Comparison options (docs/architecture.md §8). expand_repeats defaults to false (opt-in — see docs/PLAN.md 'Changed decisions'); normalize_pitch, ignore_articulations, part_filter, measure_range all d…
- `reference_xml` (string, required): Reference MusicXML document as a string
- `target_xml` (string, required): Target MusicXML document as a string, compared against the reference

### `list_capabilities` (~19 tokens)

List supported formats and available tools for this server

### `health_check` (~51 tokens)

Check that the server and all its dependencies are working correctly. Runs a self-comparison smoke test and returns a structured status summary. Ask your AI assistant to run this tool to confirm the server is set up correctly.

## Diagnostics

Captured diagnostic sections: Provenance, Install scripts, Dependencies. The full working is on the page: https://verifymcp.io/servers/raulkivi-comparer-mcp/comparer-mcp#diagnostics

## Score history

- 2026-10-01: 82
- 2026-09-30: 82
- 2026-09-29: 82
- 2026-09-28: 82
- 2026-09-27: 71
- 2026-09-26: 71

## Common questions

### What is the MusicXML Comparer MCP server?

MusicXML Comparer is an MCP server listed in the public MCP registry as io.github.raulkivi/comparer-mcp. Music-aware, multi-level comparison of two MusicXML files. This page covers its PyPI package (comparer-mcp).

### Is the MusicXML Comparer MCP server safe to use?

MusicXML Comparer scores 82 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 1 October 2026. Its build provenance is signed and verified. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the MusicXML Comparer MCP server expose?

MusicXML Comparer exposes 8 tools: compare_musicxml, compare_musicxml_files, quick_similarity, list_changes, generate_comparison_report, and 3 more. Their descriptions and schemas cost roughly 905 tokens of context every time the server is loaded.

### Is the MusicXML Comparer MCP server still maintained?

MusicXML Comparer is still listed as active in the MCP registry. We last reached this channel on 1 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

### What licence is the MusicXML Comparer MCP server under?

MusicXML Comparer declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.

## Links

- PyPI project: https://pypi.org/project/comparer-mcp/
- Socket report: https://socket.dev/pypi/package/comparer-mcp
- Repository: https://github.com/raulkivi/sheet-music-mcp
- Changelog RSS feed: https://verifymcp.io/servers/raulkivi-comparer-mcp/comparer-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/raulkivi-comparer-mcp/comparer-mcp.json
- HTML version of this page: https://verifymcp.io/servers/raulkivi-comparer-mcp/comparer-mcp