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

Annotations already declare readOnlyHint=true, and the description adds useful context beyond that: it returns item-level details including call number, location, and the circulation status of each copy. It does not contradict the annotations and provides a clear picture of what the read operation yields.

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?

The description is a single, dense sentence that front-loads the purpose and immediately provides the key return summary. Every word earns its place, with no redundant or filler content.

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 one-parameter read-only tool, the description adequately covers purpose and return content (item-level call number, location, availability/checkout status). Although there is no output schema and error behavior is not mentioned, the description provides enough for an agent to invoke the tool correctly in typical use.

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% for the single parameter, and the schema already explains that biblio_id comes from search_books results. The tool description only restates 'specific book' and adds no extra parameter semantics, so the schema carries the burden.

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 uses a specific verb ('check') and resource ('a specific book by its biblio_id'), clearly stating the tool's scope. It also lists the return details (call number, location, availability), which distinguishes it from the sibling search_books that finds books rather than checking availability.

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 implies usage after obtaining a biblio_id from search_books, especially through the parameter description ('The biblio_id from search_books results'). However, it does not explicitly state when to use this tool versus search_books or mention alternative/exclusion scenarios, so it stops short of a 5.

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

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

With readOnlyHint annotation already signaling a safe read operation, the description adds value by disclosing that the tool returns matching books with biblio_id, which is not in the schema. It also connects to check_availability, though it doesn't mention rate limits or error behavior; for a simple read-only search, this is adequate.

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?

The description is a single, well-structured sentence that front-loads the main action, then explains the output and downstream usage. It contains no superfluous words and is well-organized.

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 search tool with three parameters and a sibling, the description covers the essential purpose, output (biblio_id), and relationship to check_availability. It does not specify defaults for limit or search_type, but those are fully documented in the schema, so no critical information is missing.

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?

All three parameters (query, limit, search_type) have complete schema descriptions, so the high-coverage baseline applies. The description restates the search types but adds no supplementary syntax, examples, or parameter-specific behavior beyond the schema.

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 uses a specific verb 'Search' targeting the GBS library catalog, enumerates search dimensions (title, author, ISBN, subject, or keyword), and explains the output (biblio_id) for use with check_availability. This clearly distinguishes its role from the sibling tool.

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 implies a clear workflow by stating 'for use with check_availability', indicating that this tool is a precursor for availability checks. It lacks explicit when-not-to-use instructions but provides enough contextual guidance for an agent to understand when this tool is appropriate.

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