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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is covered. The description usefully adds the cross-tool dependency on siteId, which annotations cannot express, but says nothing about return shape, whether a project with no sites errors or returns empty, or whether projectId must exist.

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 short sentences, zero padding, with the core action stated first and the downstream rationale second. Nothing could be removed without losing information.

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 simple read-only one-parameter list tool with no output schema, the description covers the two things that matter most: what it returns conceptually and why you'd call it. It remains incomplete on the required identifier format and on what the returned list contains (IDs, names, count), which the agent must discover at call time.

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?

There is one parameter and schema description coverage is 0%, so the description must carry the entire burden. It only implies projectId scoping via the phrase 'in a Project' and never explains the expected identifier form (numeric ID vs. slug vs. opaque string) or how to obtain a valid value.

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 websites in a Project.' An agent can immediately tell this is the site-enumeration tool and can distinguish it from list_projects (projects) and list_bing_sites (Bing-connected sites). It stops short of explicitly contrasting those siblings, so not a 5.

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?

'Most tools need a siteId from this list' explicitly establishes the call-order dependency, which is the key usage decision for this tool — call it before other site-scoped tools. However, it gives no exclusions or guidance on when a different listing tool (e.g. list_bing_sites) is the right choice instead.

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