Track a SMKlog shipment

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

Annotations already mark this as read-only, idempotent, and non-destructive, and the description adds substantial behavioral detail: it returns delivery status, latest scan events, and estimated date; it normalizes tracking numbers by removing spaces/hyphens and ignoring case; and it documents exact error responses such as tracking_number_required and tracking_not_found with status 'not_found'.

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 long but every clause earns its place: scope, return value, exclusions, parameter rules, normalization behavior, carrier format expectations, and error conditions. It is front-loaded with the core action and return, then modularly covers constraints and edge cases without redundancy.

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 single-parameter read-only tool with an output schema, the description is complete: it covers input requirements, normalization, validation thresholds, error responses, result shape, and sibling relationships. There is no missing information an agent would need to decide when to call it or to interpret a successful or failed call.

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 greatly exceeds that by explaining that tracking_number is the only key, how it is cleaned, acceptable carrier formats, and the minimum length rule. This gives an agent actionable semantics far beyond the schema's simple 'Carrier tracking number from the SMKlog receipt or label page'.

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 clear and specific verb ('Track') and resource ('a shipment whose shipping label was bought on smklog.com, by carrier tracking number'), then sharpens the scope by explicitly saying it is not a universal tracker for arbitrary USPS/UPS/FedEx/DHL numbers. This distinguishes it from generic trackers and from unrelated pricing siblings.

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?

The description explicitly says when to use it ('SMKlog labels only'), when not to use it ('not a universal tracker'), and names a related flow ('When the label was bought through a create_checkout_link session, get_checkout_status hands back this number at label_ready'). It also states that pricing tools are unrelated and that no order id or email is needed or accepted.

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