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

The annotations already establish read-only, idempotent, non-destructive behavior, and the description adds useful context that the service is free and requires no key. It does not discuss rate limits or error behavior, but it enriches the safety and access profile beyond the structured 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?

The description is front-loaded with the trigger condition, then the lookup format and return fields, then an example call. Every sentence adds distinct value and there is no filler.

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 simple two-parameter lookup with an output schema, the description covers when to use it, what it accepts, what it returns, and the optional history flag. It is complete enough for an agent to invoke correctly without needing to inspect the schema.

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 0%, so the description carries the full burden and does so well: query accepts a registration number in RS-XXXX-XXXX format or a handle, and history optionally returns the full history report. The example call makes both parameters concrete.

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 precise verb and resource: looking up an agent registration by number or handle, and enumerates the returned fields. It is very clear what the tool does, but it does not explicitly differentiate itself from nearby siblings such as kya_lookup or check_license.

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?

It gives a clear usage context: call before trusting, paying, or hiring an agent you have not worked with. It does not name alternative tools or state when not to use this one, so it stops short of full routing guidance.

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