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

Annotations already declare readOnly, idempotent, non-destructive and open-world behavior, so the safety profile is fully covered without the description. The description adds nothing further, such as what happens with an unknown or malformed announcement number, so it meets only the lower bar set by rich annotations.

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?

One short, front-loaded sentence with no filler; the action and identifier come first. It is efficient, though it is terse enough that a small amount of routing context could have been added without bloat.

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?

This is a simple single-record fetch: one required parameter fully documented, annotations covering the safety profile, and an output schema so return values need not be described. The only missing element is failure behavior for a bad announcement number, which is minor here.

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?

There is a single parameter with 100% schema description coverage and an example, so the schema fully documents the input. The description only restates that the announcement number is the key, adding no format or validation detail beyond structured data.

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 and resource ('Fetch a single announcement') plus the key identifier, which clearly separates it from the bulk-oriented usajobs_search. It stops short of naming the sibling it is not, so it does not reach the top band.

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 word 'single' implies this is the lookup path when you already have an announcement number, in contrast to a search. There is no explicit when-to-use/when-not statement or named alternative, so the guidance is only implied.

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