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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It explains that data is live from the API, never cached or presented as live, that the two counts are never summed or swapped, and that a fetch failure yields a distinct UNREACHABLE state. This is unusually rich and explicit.

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 dense but front-loaded with the core purpose, and each sentence conveys necessary semantic, failure, or freshness information. There is no filler; every clause supports correct invocation and interpretation.

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 or annotations, the description fully compensates by covering return values, label meanings, freshness dates, and error behavior. An agent has enough information to invoke this tool and interpret its result without ambiguity.

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 tool takes zero parameters, and the empty input schema with additionalProperties: false fully documents this. The description adds no parameter-level detail because none is needed; the 0-parameter baseline of 4 applies.

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?

Clearly identifies the resource ('Live GSPC board totals'), the source endpoint, and the exact return values (slot count, measured count, as_of dates). The detailed slot/measurement distinction and UNREACHABLE state make the tool's role unambiguous relative to the sibling list.

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 implies this tool is for live measured board totals, but it never explicitly states when to prefer it over siblings or when not to use it. The only indirect exclusion is 'never certify,' leaving the agent to infer usage from the resource name.

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