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

Annotations already declare openWorldHint=true, idempotentHint=false, and destructiveHint=false; the description adds one genuinely useful signal, the premium-subscription requirement, which is an entitlement gate an agent cannot infer from the schema. It does not explain why the call is non-idempotent (AI generation may vary between identical calls) or whether calls consume quota, so the added context is partial.

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 with the capability stated first and the constraint second; no filler and no repetition of schema or annotation content. Every clause carries information.

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?

An output schema exists, so return values need no explanation, and the schema covers both inputs. The description supplies the fallback positioning and the subscription requirement, leaving only minor gaps around cost/latency and explicit preference ordering versus specialized tools.

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% with only two parameters, so the schema fully documents 'query' (natural-language request, English/French) and 'context'. The description adds nothing about either parameter, so 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 capability (universal calculator) and explicitly positions it as the fallback for calculations 'not covered by specialized tools', which distinguishes it from the hundreds of calculate_* siblings. The 'AI-powered' framing is slightly promotional but the catch-all role is unmistakable.

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?

'Handles any calculation not covered by specialized tools' functions as an implicit selection rule: reach for a domain-specific sibling first, then fall back here. No explicit 'do not use for X' guidance or examples, but the routing condition is clear enough to act on.

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