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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, so the safety profile is covered. The description adds meaningful context beyond that: self-hosted official CDE aggregate snapshot, bounded results, coverage percentage, provenance, and the critical caveat that these are crimes known to law enforcement only.

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?

Three sentences, front-loaded with scope, then output fields, then usage examples and exclusions. Dense but each sentence carries information; the field enumeration is slightly list-heavy but useful given no output schema.

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, the description helpfully enumerates returned fields (offenses, clearances, rates, populations, coverage, pagination, provenance), and the law-enforcement-only caveat is important. Scope and usage are well covered, leaving only minor gaps.

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 coverage is 100%, so the schema already documents all seven parameters including the enum values and the two-letter state pattern. The description names returned fields but adds no syntax or constraint detail beyond the schema, so 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 (return) plus resource and scope: a bounded monthly trend for one state and one FBI summarized UCR offense category. This clearly distinguishes it from siblings like fbi_cde_national_crime_trend, fbi_cde_compare_state_to_national, and fbi_cde_state_month_snapshot.

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?

Gives concrete example queries ('California violent-crime trend in 2023', 'monthly motor vehicle theft reported in Texas') and an explicit exclusion ('never use for cross-state rankings or individual decisions'). It does not name the specific sibling to use instead, so it stops short of full routing guidance.

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