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

The annotations already cover safety (readOnly, idempotent, non-destructive) and the output schema covers the return shape. The description adds useful scope: it returns ALL sub-elements as a reference list, so the agent knows there is no filtering or pagination logic to reason about. It adds modest but real value beyond the structured fields.

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?

It is one sentence, front-loaded with the verb and resource, and the trailing purpose clause earns its place by routing the agent. There is no boilerplate.

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, static, zero-parameter reference lookup. The annotations supply the safety profile and the output schema supplies the return structure. Nothing an agent needs in order to call it correctly 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?

The tool takes zero parameters, so there is nothing to document, and the baseline applies. The description correctly implies the tool takes no inputs because it returns the whole list.

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 and resource: it returns the USAJOBS reference list of federal agency sub-element codes and names. That is more specific than the name alone, which only says 'agencies'. It doesn't explicitly contrast itself with the sibling reference lists (list_occupational_series, list_pay_grades), but the resource is unambiguous.

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?

It gives a clear context: use it to resolve agency codes returned by the search tool. It stops short of when-not-to-use guidance or naming alternatives. Still, for a zero-parameter lookup, the intended moment of use is clear.

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