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

Annotations already cover read-only, idempotent, and non-destructive traits. The description adds genuine behavioral context: it reads cached data, performs no screening, and is free. These details help agents understand cost and side effects beyond what annotations provide.

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?

Two short sentences carry all necessary information with no filler. The core purpose is front-loaded, followed by the exclusion and cost note. Every clause 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?

For a zero-parameter, read-only status tool, the description fully covers what the call returns, what it does not do, and that it is free. No output schema exists, but the described return value (counts and timestamps for four lists) is sufficient for an agent to invoke and interpret 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?

The tool has zero parameters, so there is nothing for the description to explain about inputs. The empty input schema plus 100% schema coverage means no parameter documentation is needed; a baseline score of 4 applies for zero-parameter tools.

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 states a specific function: 'Counts and last-update timestamps for all four lists in the cache.' It explicitly distinguishes itself from screening tools with 'No screening is performed,' separating it clearly from sanctions_screen_* and other sanctions lookup siblings.

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 clearly signals when not to use this tool ('No screening is performed'), which is a valuable exclusion for agents considering sanctions tools. However, it does not name a specific alternative to use when screening is needed, so it stops short of explicit routing guidance.

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