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

The description explains why readOnlyHint=false matters: a free link consumes one of the account's daily free files and a fast link draws down the account balance — a real side effect not expressed by the annotations. It also confirms repeat calls return the same link, consistent with idempotentHint=true. It omits error behavior for non-succeeded jobs and any auth/permission requirements.

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 short sentences, front-loaded with the core action and free of filler. The tier explanation partially restates the schema's own tier description, a minor redundancy, but nothing is padded.

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 two-parameter tool with an output schema, this covers the key unknowns: the succeeded-job precondition, the cost model per tier, and idempotency. Missing only failure-mode behavior (invalid or unfinished job_id) and auth requirements.

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 tier values are already documented; the baseline is 3. The description goes slightly beyond by tying tier to consumption behavior (quota vs balance) and by noting that the same job_id + tier pair yields the same link, adding per-parameter behavioral meaning.

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 and resource ('Get the download URL') and adds a real precondition ('of a succeeded job'), which meaningfully narrows scope. It does not, however, distinguish itself from close siblings like download, check_link, or start_download, leaving the agent to infer the boundary.

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 only implied: the agent can infer this is called after a job has succeeded, and the tier sentence hints at the free-vs-paid tradeoff. There is no explicit when-to-use-vs-alternatives guidance, so the agent still cannot tell whether this replaces or precedes 'download' or 'check_link'.

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