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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is covered. The description adds substantial behavioral context beyond that: the acuity formula, the 300 ppi cap, the distinction between acuity-suggested ppi and 300 ppi, and the verdict returned when pixel dimensions are supplied.

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-loads the purpose in the first sentence and is reasonably efficient, but the formulas and caveats make it a dense single paragraph. Every sentence carries useful information, though bullet-style structuring would improve readability.

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?

Covers the core computation, optional inputs, return values, and key caveats despite the absence of an output schema. Minor gaps remain around precise verdict criteria and error handling, but the agent has enough to invoke it correctly.

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 baseline is 3. The description adds meaning by tying parameters to the formulas (pixels = size in inches × ppi) and explaining how viewing_distance feeds into the acuity calculation, which helps an agent understand parameter roles rather than just their names.

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: 'Calculate resolution for print', and clarifies 'DPI here means image pixels per inch'. It is clear what the tool does, though it does not explicitly differentiate itself from related siblings such as calc_print_spec or convert_paper_size.

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 clear context for when to use it — print resolution calculation — and when to lower ppi for large-format work, plus the caveat that the vendor's stated minimum wins. It does not name alternative tools or explicitly exclude use cases, so it falls 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.