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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds genuinely new behavior: the response fields (reporting population, full population, coverage percentage), an explicit warning emitted below 90 percent coverage, pagination, and provenance. It also flags an interpretive limit ('coverage is not data quality proof'), which is behavioral guidance annotations cannot carry.

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?

Front-loaded with the core action and return contents, then the use cases, then the caveat. Dense but each sentence earns its place; the second sentence is long and carries several distinct ideas at once.

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?

There is no output schema, so the description correctly compensates by enumerating what is returned (populations, coverage percentage, warning, pagination, provenance). Combined with the usage framing and the interpretation caveat, an agent has everything needed to call and correctly contextualize the result.

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% and every parameter is documented there, including the two-letter state constraint and the YYYY-MM month format. The description adds only the scoping phrase 'for one state,' so the schema does the heavy lifting and the baseline 3 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?

States a specific verb and resource: 'Inspect monthly FBI UCR population coverage for one state in LiveDataLink's self-hosted CDE aggregate snapshot.' It also situates itself against the crime-trend sibling ('before interpreting its summarized crime trend'), so an agent can distinguish it from fbi_cde_state_crime_trend without opening a schema.

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 concrete trigger phrasings ('was California's 2021 FBI reporting coverage complete?', 'find low-coverage months') and a clear role: 'to qualify an analysis' and 'must accompany, not replace, methodological review.' No named alternative tool or explicit when-not condition, so it stops short of a 5.

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