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

With no annotations, the description carries the full burden and does so well: it discloses the data source (daily USAspending snapshot), the time scope (latest published FY plus 3-year trend), that freshness/FY are echoed in the response, federal-only coverage, and two real limitations (partial in-progress FYs, intel-agency spend never published).

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?

Front-loaded with the purpose and the question it answers, then the payload, then caveats. Dense but every sentence contributes; slightly long, with the caveat clause compressed into one run-on sentence.

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?

There is no output schema, so the description must describe returns — and it does: obligations, trend, top vendors, top NAICS, plus the FY/freshness echoed back. Combined with the coverage caveats, an agent has everything needed to call and interpret this tool correctly.

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 100% for the single required `agency` param, including format examples (name, acronym, code), so the schema already does the heavy lifting. The description reinforces this with "Good queries name one agency, e.g. agency='HHS'" but adds no new syntax or constraints beyond the schema.

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 (profile a federal agency's contract spending) and enumerates the exact payload: total obligations, 3-year trend, top 10 vendors, top 10 NAICS categories for the latest published FY. This is clearly distinguishable from siblings like find_expiring_contracts or incumbent_lookup without opening any schema.

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?

Explicitly frames the use case ("before a first call", answering "what does this agency actually buy, and from whom?") and gives query-shaping guidance ("name one agency, e.g. agency='HHS'"). It does not name alternatives or state when not to use it, so it stops short of a 5.

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