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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds real behavioral value beyond that: it discloses the return payload (results, a shareable link, accepted inputs with current values) and the default-filling behavior for omitted inputs. It is silent on error handling for unknown slugs or invalid input keys.

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, all load-bearing, with the core action stated first and the return payload, usage scope and input-key convention following in priority order. No filler or restatement of the title.

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, but the description itself enumerates the return contents, so the agent knows what comes back. For a two-parameter tool with full schema coverage and full annotation coverage, nothing needed to call it correctly is missing.

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 baseline is 3, but the description adds genuine semantics: input keys vary per calculator, they are discoverable via search_calculators, and omitted inputs fall back to the calculator's defaults. That is information the schema cannot express.

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 ('Runs one Calcupedia calculator with its verified formulas') and scopes the domain (finance, health, math, date, unit conversion). It also distinguishes itself from search_calculators by noting that tool lists the input keys this one consumes.

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 a clear condition for use ('questions that need exact figures the user can check') and points to search_calculators as the source of input keys. It does not, however, explain how it differs from the sibling 'calculate' tool, leaving an obvious overlap unresolved.

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