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

The annotations (readOnlyHint=true, destructiveHint=false, idempotentHint=true) already disclose the safety profile, so the description doesn't need to repeat it. However, the description adds no additional behavioral context beyond what the schema and annotations provide. This is acceptable but not enhanced.

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, front-loaded sentence with no wasted words. It immediately states the action, the resource, and the unique identifier, making it highly concise and well-structured.

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 lookup tool with one parameter, full schema description, an output schema, and rich annotations, the description is sufficient. It doesn't need to explain return values or safety because those are covered by structured data.

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?

The schema description coverage is 100%, so the parameter 'announcement_number' is already well-documented. The description adds minimal meaning beyond what the schema provides, just restating 'by announcement number.' Baseline 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 uses a specific verb ('Fetch') and resource ('a single announcement') with a clear identifier ('by USAJOBS announcement number'). This clearly distinguishes it from sibling tools like list_agencies or search, which serve different purposes.

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 the usage context: you would use this tool when you have a specific announcement number and need the corresponding announcement. While it doesn't explicitly mention alternatives or exclusions, the context is clear enough for a get-by-ID tool.

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