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

Annotations already carry readOnlyHint=true, idempotentHint=true, and openWorldHint=false, so the safety profile is covered. The description adds useful behavioral context beyond that: the output composition (slug, URL parameters, languages/currencies) and the filtering semantics shown in the example, which clarifies that 'all' is the default scope. No contradiction with annotations.

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 dense sentences plus a compact example. The primary purpose is front-loaded, the sequencing guidance comes second, and the example is concrete with zero filler. Every element 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 read-only list tool with one optional enum parameter and an output schema, the description covers everything an agent needs: what is returned, when to call it (before build_calculator_link), and how filtering behaves. The output schema handles return structure, so nothing critical 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 description coverage is 100% and the enum parameter 'group' already has a per-value description, so the schema carries the semantic weight. The description's example ({"group":"history"}) adds a concrete illustration but no meaning beyond what the schema already states.

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?

"List every SmartMoney77 calculator with its slug, accepted URL parameters and supported languages/currencies" names a specific verb, resource, and the exact output fields, which fully clarifies what the tool does. It distinguishes itself from siblings by naming build_calculator_link and implicitly separating from the individual calculator tools (compound_interest, fire_number, etc.) that it lists.

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?

"Call this before build_calculator_link" is explicit sequencing guidance that tells the agent when this tool is the right choice. The example further illustrates the contextual use of the group filter, though it does not enumerate when-not conditions against all 13 siblings — confusion with those is unlikely given the clear list/discovery purpose.

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