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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds genuine context beyond that: results are sorted latest or oldest and are paginated, and it identifies the required key/tracker_type pair. It stops short of describing result volume, paging limits, or how many scans a shared key typically surfaces.

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 compact sentences with the purpose and required inputs front-loaded. The final sentence is slightly advisory rather than operational but is short and adds investigative framing, so little 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?

An output schema exists, so return values need not be explained, and annotations cover the safety profile. The description supplies purpose, the required key pair, ordering, and pagination, leaving only the permitted tracker_type values as a notable gap.

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 0%, so the description must carry the load. It explicitly names tracker_type and key as the required inputs, states the sort options, and signals pagination, which maps to page/limit. However, it never enumerates or explains valid tracker_type values, which is the one piece an agent most needs and cannot infer.

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 gives a specific verb and resource ("Find scans that embed a given tracking or site key") and disambiguates the key concept with concrete examples (analytics ID, CAPTCHA site key). It distinguishes itself from the aggregate sibling get_top_tracking_keys by framing this as a lookup by a supplied key, though it never names that sibling.

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 tool is for locating scans sharing a tracking/site key. There is no explicit when-to-use guidance, no exclusions, and no mention of the related aggregate tool get_top_tracking_keys or how to choose between them. The closing note about shared keys tying sites to one operator hints at the investigative use case but doesn't state it as guidance.

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