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

With no annotations, the description carries the full burden of disclosing behavior. 'Fetch' implies a read-only operation, and 'full grant record' signals comprehensive output. However, it does not mention error behavior, authentication, or whether the ID format has restrictions, leaving some ambiguity for a tool with no annotation safety net.

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?

One short sentence that leads with the action and states both the resource and the key input. Every word earns its place; no filler or redundancy.

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 one-parameter tool with an output schema, the description covers the essential retrieval action. It lacks any usage guidance relative to sibling tools and does not state what makes the record 'full', so completeness is adequate but not strong.

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 provides no description for opportunity_id, but the description clarifies it as a 'Grants.gov opportunity id', which gives the parameter meaningful context beyond the bare type string. For a single parameter this is sufficient to guide invocation.

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 a concrete resource ('full grant record') tied to a 'Grants.gov opportunity id'. This clearly distinguishes it from search-oriented siblings like search_grants, though it does not explicitly name the distinction.

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?

No guidance is provided on when to use this tool versus alternatives such as search_grants or get_contract_details. An agent must infer that this is for retrieving a single record by ID rather than searching, which is not explicitly stated.

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