Open Census MCP Server

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

Without annotations, the description carries the full burden and successfully discloses that the tool returns statistical nuance (margins of error, fitness-for-use caveats) rather than raw data. However, it lacks explicit safety hints (though 'Retrieve' implies read-only) or error behavior documentation.

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?

Four sentences with zero waste: purpose statement, return value specification, prerequisite workflow, and interpretation warning. Information is front-loaded and every sentence earns its place.

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 lack of output schema, the description adequately explains return values (estimates, margins of error, pragmatics field) and contextualizes the statistical nature of Census data. Minor gap in not addressing rate limits or error states, but strong overall for a 7-parameter data retrieval tool.

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?

With 100% schema description coverage, the schema fully documents all 7 parameters including FIPS code formats and wildcard usage. The description adds no parameter-specific semantics, which is appropriate given the high schema coverage baseline.

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 the specific verb 'Retrieve' with the resource 'Census data' and clearly distinguishes this from sibling get_methodology_guidance by stating it returns 'statistical methodology guidance,' 'estimates, margins of error, and pragmatic context'—indicating this is the data retrieval step as opposed to the guidance step.

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?

Provides explicit workflow sequencing ('Use this after grounding with get_methodology_guidance') and mandatory post-processing instructions ('Always review the pragmatics field before interpreting results'), clearly establishing when and how to use the tool relative to its sibling.

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