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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does reveal that the destination is returned only if the link is active ('iff active'), which is a useful conditional. However, it does not disclose that both url and code are optional per the schema (implying at least one must be provided), nor does it mention error cases or explicitly confirm the operation is read-only. The description is thin on behavioral details beyond the conditional.

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 a single, concise sentence that front-loads the action ('Resolve an apex short URL or code') and the result ('to link status'). Every word earns its place, and it avoids redundant phrasing. It is appropriately sized for the tool's simplicity.

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?

The tool has an output schema, so the return structure is covered. The description captures the core behavior (resolving to status and conditional destination) and is adequate for a simple lookup. The only notable gap is the schema's 0 required parameters conflicting with the implied need to supply at least one of url/code; the description does not explicitly enforce or clarify this, but it does say 'or', which hints at a choice. Overall, it is sufficiently complete given the output 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 coverage is 100% – both url and code have descriptive text, with the schema noting 'Short code if URL not provided'. The description adds the word 'apex' but does not define it or add meaning beyond the schema. It clarifies the two inputs are alternatives, but this is already implied by the schema's phrasing. The description adds marginal value, so 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?

The description clearly states the tool resolves a short URL or code to link status, with a conditional destination. The verb 'resolve' and resource are specific, and the purpose is distinct from siblings like shorten_url, get_link, or disable_link, which manage or create links. It is unambiguous about what the tool does.

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 implies the use case: when you have a short URL or code and want to check its status. It does not explicitly name alternatives or state when not to use it, but the sibling set (shorten, update, disable, analytics) makes it clear this is for resolution only. The guidance is implicit but adequate, lacking explicit exclusionary notes.

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