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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered; the description still adds real behavior: a hard 30-day window, newest-first ordering, Vietnam timezone on timestamps, and a running/done status field. It omits what happens when more scans exist than the limit allows (truncation vs pagination), which is the one behavioral gap.

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?

Two tight sentences with no filler: the first front-loads scope, ordering and return shape, the second front-loads the next step. Every clause carries information an agent needs.

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 correctly takes on the job of enumerating returned fields and their semantics (timezone, ordering, status), which is the main completeness burden here. The only shortfall is the unstated paging/truncation behavior for a list capped by 'limit'.

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% for the single 'limit' parameter, so the schema already carries the meaning and the baseline applies. The description never mentions the limit or how it interacts with the 30-day window and newest-first ordering, adding nothing beyond the schema.

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 ('The user's keyword scans') plus scope ('last 30 days, newest first') and enumerates the returned fields (scan id, start time, keyword count, running/done). It also routes to the sibling that consumes the output ('Use the scan id with spywin_get_scan_results'), so an agent can separate this from get_scan_results and get_scan_status without opening a schema.

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?

Gives clear forward guidance: call this to discover scan ids, then pass one to spywin_get_scan_results. It does not address the alternative diagnostic siblings (spywin_get_scan_status, spywin_get_my_scanner_status) or state when this tool is the wrong choice, so it falls short of full when/when-not coverage.

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