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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so safety is covered. The description adds behavior the annotations do not: the not-found outcome for unregistered numbers and the prerequisite of prior registration, plus the shape of the returned checkpoint data. It omits pagination/latency details but is solid for a read tool.

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-loaded with the resource and return shape, then constraints, then the fallback action. Well packed with almost no filler, though the trailing raw endpoint string ('GET /trackings/get?tracking_numbers=') adds little for an agent that already has the schema.

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?

No output schema exists, but the description compensates by naming the returned fields (origin_info/destination_info trackinfo with date, status, details, location). Combined with the disambiguation guidance and the registration prerequisite, an agent has everything needed to call 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 coverage is 100%, so the baseline is 3, but the description adds genuine meaning about courier_code — it is needed to disambiguate when one number maps to several couriers, which the schema only illustrates with examples. Only 'lang' goes unexplained beyond the schema.

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+resource with scope: 'The full tracking record of one shipment already registered in the account', and even enumerates the returned checkpoint structure. It is clearly distinguishable from siblings like trackingmore_list_trackings (many shipments) and trackingmore_create_tracking (writes).

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 explicit lookup conditions ('by tracking number; add courier_code if the number is used by several couriers') and routes to the correct sibling when the precondition fails: 'A number that was never registered is not found: register it with trackingmore_create_tracking first.' This covers when-to-use and the alternative path.

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