Search download sites

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

Annotations already cover read-only/idempotent/open-world safety, but the description adds real behavioral context: results preserve each source's own relevance order and are grouped by source, no file links are ever returned, and failing sources appear under an `errors` field. That is meaningful disclosure beyond the annotations.

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 tight sentences, front-loaded with what the tool returns, then ordering behavior, then the download-handoff caveat and error reporting. No sentence is wasted.

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?

With no output schema, the description carries the return-value burden and does so well: it names the metadata fields, ordering, grouping, and the errors field. Complete enough to call correctly, though it could note result-volume limits.

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 page, query, sources, and per_source are fully documented in the schema. The description adds negligible parameter detail beyond 'by name', so the 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?

States a specific verb+resource ('Search the download sites by name') and enumerates the returned metadata fields, so the agent knows exactly what this produces. It does not explicitly name or contrast with siblings like dl_latest or dl_item, leaving that differentiation to inference.

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?

It implies the follow-up path by stating 'Open the item page url yourself to download; this server never returns file links,' which effectively routes the agent to dl_item. However, it never states when to prefer this tool over dl_latest or dl_item, so usage is only implied.

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