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

readOnlyHint=true already tells the agent this is a safe, non-mutating read. The description adds that results carry CCLI number, categories and locations, which is useful output context, but it says nothing about pagination limits, result caps, or required auth beyond what the annotations and schema already cover.

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?

Two compact sentences with the core capability front-loaded and the API mapping ("Elvanto: songs/getAll") trailing. Nothing is wasted, though the endpoint string is marginally less useful to an agent than a scoping or pagination hint would be.

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 read-only, fully documented 6-parameter list tool with no output schema, the description covers purpose, filter dimensions, and the shape of returned data. Only pagination behavior (defaults, caps, how to page through results) is left unaddressed, which is a minor gap.

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 title, artist, lyrics, page, page_size and files are all documented in the schema itself. The description restates title/artist/lyrics filtering but adds no matching semantics, defaults, or format details beyond the schema, 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?

The description states a specific verb and resource ("List or search the song library") and names the retrievable fields (CCLI number, categories, locations), so an agent knows exactly what it returns. It does not explicitly distinguish itself from elvanto_list_song_arrangements, which is a closely related sibling, so it stops short of a 5.

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?

"List or search ... by title, artist or lyrics" implies when the tool is appropriate (any song-library lookup with optional filters), but there is no explicit when-not guidance or reference to alternatives such as elvanto_list_song_arrangements. Usage is inferable but not stated.

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