US Government Open Data MCP

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

Annotations provide readOnlyHint=true, and the description adds valuable context beyond that: it specifies the data is 'provisional,' 'updated weekly,' covers '2020–present,' and includes 'percent_of_expected_deaths.' This enhances transparency about data recency, scope, and key metrics without contradicting annotations.

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 highly concise and front-loaded, with three sentences that each add critical information: purpose, data recency/scope, and key metric. There's no wasted text, and it efficiently communicates essential details in a structured manner.

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 tool's moderate complexity (3 parameters, read-only operation) and lack of output schema, the description provides strong context: it clarifies the data type, temporal scope, update frequency, and key output field. However, it doesn't detail response format or pagination, leaving minor gaps for a read operation.

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%, so the schema fully documents parameters. The description doesn't add specific parameter semantics beyond implying state and year filtering through its purpose statement. This meets the baseline score of 3, as the schema handles parameter details adequately.

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's purpose with specific verbs ('Get weekly provisional death counts') and resources ('by state — COVID-19, pneumonia, influenza, and total deaths'). It distinguishes itself from sibling tools like 'cdc_causes_of_death' and 'cdc_death_rates_historical' by specifying it provides weekly provisional counts with excess mortality detection.

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 usage context by stating 'THIS IS THE MOST CURRENT CDC MORTALITY DATA — updated weekly, covers 2020–present,' which suggests when to use it for recent data. However, it doesn't explicitly state when to choose this tool over alternatives like 'cdc_mortality_rates' or provide clear exclusions, leaving some ambiguity.

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