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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower; the description still adds the required Sites.Read.All delegated scope, which no annotation conveys. It does not disclose result limits or paging behavior, keeping it short of a 5.

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, front-loaded with the core action, then the mode distinction, then the auth prerequisite. No filler or restatement of the name.

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 adequately implies a list of sites and covers auth scope and mode switching. It omits the meaning of 'top' and any return/pagination detail, which is a minor gap for a simple two-parameter list tool.

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 coverage is 0% and neither parameter is described in the schema. The description explains 'search' well (walks the tenant index) but says nothing about 'top', implying a page-size/count semantic that is left to guesswork. Partial compensation only.

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 (List) and resource (SharePoint sites), plus a scope qualifier ('the authorized user can read'). It also distinguishes its two modes (default followed sites vs. search-driven tenant walk), so an agent can tell it apart from siblings like list_libraries or import_sharepoint_list_projects without opening the 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?

Explicitly tells the agent when each behavior applies: omit 'search' to get followed sites, pass 'search' to walk the tenant index. That is clear mode-selection guidance, though it names no alternative sibling tool for the 'find sites elsewhere' case.

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