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

Annotations already carry readOnlyHint=true, so the read-only safety profile needs no restatement, and the description adds the scoping intent. However, it discloses no additional behavioral traits — no mention of pagination outcomes, ordering, response shape, or that fully confirming non-membership requires following cursors across pages. The schema's cursor/limit descriptions cover the mechanics, but the description itself adds little behavioral value beyond the annotation.

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 with zero waste. The core action is front-loaded and the second sentence earns its place by supplying the motivating use case. Nothing is repeated from the title or schema, and there is no filler.

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 low-complexity paginated list tool, this is nearly complete: the schema fully documents all parameters including pagination mechanics, annotations cover the read-only safety profile, and the description supplies the when-to-use intent. The one real gap is that the stated use case — 'confirm whether someone actually belongs' — is subtly undermined by pagination: a user on a later page would be missed on the first call, and the description doesn't warn that concluding non-membership requires sweeping all cursors.

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 description coverage is 100%: tenant_id, limit (with default and API cap), and cursor (with detailed opaque-token handling rules) are all well documented in the schema. The description contributes no parameter-specific meaning, so the baseline 3 applies per the coverage rule.

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+resource+scope — 'List the users associated with one tenant' — which is immediately distinct from inverse siblings like list_user_tenants (tenants for a user) and broader lists like list_tenants. The second sentence anchors it to a concrete reasoning task (confirming tenant membership for branding/preferences analysis), making the tool's role unambiguous without needing to open 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?

Gives a clear, explicit use case: confirm whether someone actually belongs to the tenant whose branding or preferences you are reasoning about. This is actionable context an agent can select on, but it stops short of full guidance — it names no alternatives and states no exclusions (e.g., no pointer to list_user_tenants for the inverse direction or to get_user_profile_by_id for richer profile data).

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