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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds useful context about what is returned (CCLI number, categories, locations), which matters since there is no output schema, but it omits pagination behavior and the fact that songs/getAll may paginate across the library.

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 covering purpose, search fields, and return contents, followed by a short API mapping. Efficient with no filler, though the 'Elvanto: songs/getAll' reference adds little for an agent.

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 6-parameter, all-optional read tool with no output schema, the description adequately covers what the tool does and roughly what it returns. It is close to complete; minor gaps are the absence of pagination notes and sibling differentiation.

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 description coverage is 100%, so all six parameters (page, files, title, artist, lyrics, page_size) are already documented in the schema. The description restates title/artist/lyrics filtering but adds no format or syntax detail beyond what the schema provides, so the baseline of 3 applies.

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 (list/search) and resource (song library), and enumerates the searchable fields (title, artist, lyrics) plus returned attributes (CCLI number, categories, locations). It is clearly a song-listing tool, though it doesn't explicitly differentiate itself from the sibling elvanto_list_song_arrangements.

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 phrase 'List or search the song library' implies the tool's use case for finding songs, but no when-to-use guidance, prerequisites, or named alternatives (e.g., list_song_arrangements) are given. Usage is inferable from the description but not explicitly scoped.

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