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

Annotations already declare readOnlyHint=false, destructiveHint=true and idempotentHint=false, so the safety profile is partly covered; the description still earns credit by disclosing the concrete side effect (the arrived upload is moved onto the Mac by this call), the blocking wait with a bound, and the full state machine. One caveat: 'Safe to repeat' sits in mild tension with idempotentHint=false, although retry-safety is not strictly the same property as idempotency, so this is not a direct contradiction.

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?

Three sentences, zero filler, and front-loaded: purpose and state list first, then the side effect and wait behavior, then the retry note. The state enumeration is long but carries real routing information, so it earns its space.

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?

There is no output schema, and the description compensates by enumerating the possible return states, plus explaining the side effect and the blocking wait. It omits auth requirements and error behavior for failed/expired links, but for a two-parameter polling call it is essentially complete.

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%, so both parameters are already fully documented (link url/download_url; wait_seconds 0-50, default 20). The description's 'by its url' and its restatement of the wait bound/default add no semantics beyond the schema, so the baseline of 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?

States a specific verb+resource+key ('Returns a file link's state by its url') and then enumerates the exact state values, which is more informative than a restatement of the name. It is clearly distinguishable from siblings such as create_mac_link, read_mac_file or get_mac_job by resource, though it never names an alternative explicitly.

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?

Usage is implied rather than stated: the agent can infer this is the polling/placement call because it says an arrived upload 'is moved onto the Mac by this call' and blocks for wait_seconds. There is no explicit when-to-use, when-not, or routing to a sibling (e.g. read_mac_file once ready), so it stays at the minimum-viable level.

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