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

Annotations already cover read-only safety (readOnlyHint=true, destructiveHint=false). The description adds useful behavioral context beyond that: the list is restricted to sites SearchLink can read on the user's plan, and it reveals the specific output dimensions (access level, plan limit, Bing connection). No contradictions with 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 short sentences carry only essential information: what is listed, what to use it for, and its read-only nature. The purpose is front-loaded and every clause earns its place.

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 zero-parameter, read-only list tool, the description fully equips an agent: it identifies the resource, the filtering condition (plan access), the returned fields, and when to call it. No output schema exists, but the enumeration of returned data compensates sufficiently.

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?

The input schema has zero parameters and schema description coverage is 100%, so the schema imposes no burden. The description appropriately focuses on the output rather than parameters, matching the baseline for no-parameter tools.

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 states a specific action ('Lists'), a clear resource ('sites in the user's Search Console that SearchLink can read on their plan'), and the key data included (access level, plan limit, Bing connection status). This clearly differentiates it from siblings like search_performance or sitemaps, which target different resources or metrics.

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 gives an explicit invocation condition: 'Call first when the user has not named a site.' This tells the agent when to use the tool, but it does not name alternative tools or explicitly state when not to use it, so it falls just short of the full 'when/when-not/alternatives' criterion.

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