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

With no annotations provided, the description carries the full burden and does well: it discloses the roster-only nature, returned user fields, sorting semantics, and pagination ritual (passing next_cursor back). It does not mention rate limits or the exact ordering of 'recent' (ascending vs. descending), but these are minor for a read-only list tool.

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?

The description is well-structured and dense: purpose at the top, followed by response highlights, filter/sort semantics, pagination, and a typical call. Every sentence earns its place with no redundancy or fluff.

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?

Given that the output schema exists and the tool is a straightforward list operation, the description covers all essential aspects: result contents, filter/sort options, pagination, and a practical usage example. It provides enough information for an agent to select and invoke the tool correctly without needing to consult additional sources.

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 no parameter descriptions (0% coverage), so the description must add meaning—and it does: 'q filters by name or external id', 'sort ∈ recent | tokens24h', and pagination via cursor. The 'limit' parameter is left to inference, but its default (50) is visible in the schema and its meaning is self-evident.

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 clearly states 'List this tenant's end users' and explicitly scopes it as 'roster only, never any conversation content,' distinguishing it from session-related sibling tools. It names the resource (end users) and the action (list), making the purpose unambiguous.

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?

The description provides a concrete typical use case—'list_end_users(sort="tokens24h") to find the most active / most expensive users'—which helps an agent decide when to use it. However, it does not explicitly name alternative tools (e.g., list_user_sessions) or state when not to use it, stopping short of full when/when-not guidance.

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