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

Annotations already declare readOnlyHint and idempotentHint, so the description doesn't need to repeat that. It adds value by specifying the types of data returned (account_obligations_by_defc, parent IDV info, subaward count) and the special handling for IDV awards. It omits rate limits or auth, but for a read-only operation these are less critical.

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 well-structured: first sentence states the core purpose, then the return payload, input source, and routing to related tools. Each sentence contributes new information, and the most critical instruction (input source) is prominent. No filler or repetition.

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 single-parameter, read-only tool with an output schema, the description covers everything an agent needs: what it does, what input to pass, what data it returns, and when to use a different tool. The output schema handles return structure, so no further detail is required.

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 already documents the award_id parameter with 100% coverage, including an example and the note to use generated_internal_id. The description reiterates the same guidance without adding new semantic details. Baseline 3 is appropriate because the schema handles parameter semantics fully.

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 clearly states the verb 'Fetch' and resource 'award details', and lists specific data returned (recipient info, agency hierarchy, etc.). It differentiates from siblings by explicitly directing IDV awards to usaspending_get_idv_awards, making the purpose 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 explicitly instructs to use generated_internal_id from usaspending_search_awards, and says when NOT to use this tool (for IDV awards, use usaspending_get_idv_awards). It also mentions related tools for recipient and NAICS data, providing clear routing and exclusions.

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