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

Annotations indicate read-only, idempotent, non-destructive behavior, which the description aligns with by noting it provides reference documentation. The description adds value by detailing the scope of topics covered, going beyond annotation information.

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 concise, using a bullet list for topics and emphasizing key ones in a single paragraph. Every sentence adds useful information without 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?

Given the simple parameter (one enum) and no output schema, the description adequately explains the tool's purpose and the content of each topic. It doesn't specify return format but that's acceptable for a reference guide.

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 input schema has 100% coverage with a single enum parameter. The description adds context by explaining the content of each topic (e.g., what 'datums' includes), exceeding the schema's basic description.

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 tool provides curated reference documentation for NOAA CO-OPS concepts and parameters. It lists specific topics, distinguishing itself from sibling data retrieval tools by emphasizing its role as a reference guide.

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?

The description explicitly advises consulting this tool before constructing unusual requests, highlighting specific topics like datums, units, and data_limits. It provides clear context for when to use it, though it doesn't explicitly state when not to use it.

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