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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so "Read-only" adds nothing beyond structured data. The description says nothing about what is returned, whether missing IDs error or return empty, or what the untyped `extra` object is for.

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 fragments contain zero filler, so it is certainly concise, but brevity here comes at the cost of usefulness rather than being front-loaded information. There is no structure beyond a noun phrase and an adjective.

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?

With no output schema, 0% parameter documentation, a nested object, and an open-world read, the description leaves nearly everything an agent needs unexplained. Two words cannot cover this tool's surface.

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 0% for four parameters, including three required ones (account_id, job_id, applicant_id) plus a nested free-form `extra` object. The description gives no meaning for any of them, leaving the agent to guess at identifier formats and the role of `extra`.

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?

"One applicant" is essentially a restatement of the name/title "Get applicant" with no verb, no statement of what is retrieved or under what scoping. The singular does faintly distinguish it from the sibling list_applicants, but that is inference rather than stated purpose.

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?

There is no when-to-use guidance, no prerequisites, and no mention of list_applicants as the alternative when a collection is wanted. The agent must infer the single-record vs. list distinction purely from the word "One".

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