Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is fully covered. The description adds that content is static reference material (patterns, templates, GM lists) but says nothing about return format or size, which matters for a guide that returns lengthy notation snippets.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single front-loaded sentence with a compact topic list; every clause earns its place by telling the agent what lives behind each enum value. No redundant restatement of the tool name or annotations.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-parameter read-only lookup with no output schema, the description covers the full topic space and is sufficient to invoke correctly. The only real gap is not indicating output shape or rough length of the returned reference material.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and each enum value carries a short description, so the baseline is satisfied. The description goes beyond the enum names by explaining the substance of each topic (e.g., genres include a 3/4 minuet and lullaby, instruments include GM list plus combos), which helps the agent pick the right topic on the first call.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb-resource pair ('Reference for ABC sheet music') and enumerates the seven topic areas it covers. The agent knows this is a static knowledge lookup, though nothing in the text distinguishes it from siblings like get-strudel-guide or search-music-docs.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The parenthetical notes ('complete templates', 'what each accompaniment preset does') hint at what each topic is for, and the schema description advises starting with 'genres' or 'styles'. But the description itself gives no explicit when-to-use-this-vs-alternatives guidance, particularly against the sibling docs/search tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.