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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds real value by disclosing the shape of what comes back (per-scan timing, status, assistants, answer volume, cost) in the absence of an output schema. It does not mention pagination, result caps, or ordering, which is the remaining gap for a list endpoint.

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 sentences, front-loaded with the resource and its returned fields, followed by the routing rule. Every clause earns its place and there is no redundant restatement of the title.

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 single-parameter, non-destructive list tool with annotations covering safety, the description is nearly complete: it covers purpose, use cases, return content, and the alternative tool. Only result-volume behavior (pagination/limits) is unaddressed, a minor omission given that no output schema exists.

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?

Only one parameter exists and its schema description is fully covered (100%), including the cross-reference to list_projects for obtaining the id. The prose adds no syntax or filtering detail beyond that, 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 and resource ('List the scans of a site') and enumerates exactly what each record carries: run time, status, assistants queried, answer count, cost. It also names the sibling it is not ('for the scan in progress use get_live_scan'), so an agent can separate it from get_live_scan 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 two concrete use cases ('review spending or find a runId') and an explicit exclusion with the alternative tool to use instead for in-progress scans. Nothing about when to reach for this versus a sibling is left to inference.

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