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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), so the bar is lower. The description still adds real behavioral context beyond them: descriptions are clipped and the full Grants.gov announcement is authoritative, which tells the agent the returned text may be truncated and not to treat it as final.

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 purpose and input forms are front-loaded in the first sentence, and the usage trigger follows in the third. The middle enumeration of return fields is long, but with no output schema it is load-bearing rather than padding; only mild tightening is possible.

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?

With no output schema, the description compensates by enumerating the returned fields (eligibility, award floor/ceiling, dates, contacts, assistance listings, how to apply), and it flags the clipping caveat. An agent has everything needed to choose and call it 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 coverage is 100%, so the baseline is 3. The description goes slightly beyond the schema by tying the accepted input forms to their provenance ('numeric opportunity ID (from search_grants)'), which helps the agent know where to obtain a valid value rather than just what shape it takes.

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 ('Get the full Grants.gov record for one federal grant opportunity') and explicitly scopes it to a single opportunity. It also distinguishes itself from search_grants by naming it as the source of the ID, so an agent can route between lookup and search without opening either 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?

Gives clear usage triggers ('Use when the user asks about a specific grant, whether they qualify, or how to apply') and points to the sibling search_grants as the origin of the identifier. It does not state an explicit when-not or a rule for what to do if the ID is ambiguous, so it falls short of a full 5.

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