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

Annotations already cover read-only/non-destructive behavior. The description adds meaningful behavioral detail beyond annotations, especially that a bare number is treated as a hymn number rather than a lyrics query, and that the corpus is limited to 201 hymns.

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 short sentences, each earning its place: the first states the main search capability and scope, the second clarifies an important edge case. No redundant filler or repetition of schema details.

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 simple 2-parameter search tool with full schema coverage and read-only annotations, the description is largely complete. It could be slightly stronger by explicitly naming the return behavior or sibling distinction, but nothing essential is missing for correct invocation.

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%, so the baseline is 3. The description adds genuine value by explicitly clarifying that a numeric-only q triggers song-number lookup rather than lyric search, removing ambiguity that the schema alone leaves open.

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?

Describes a specific action: searching 원불교 성가 201곡 by title, lyrics, or number. This clearly distinguishes it from sibling tools like search_scripture or lookup_dictionary by naming the exact resource and the special numeric behavior.

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 description gives clear context for when to use the tool (when searching hymns by title, lyrics, or number) and explains the numeric-input special case. It does not explicitly name alternative tools or exclusions, but the resource scope makes the intended use apparent.

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