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

Annotations already declare readOnlyHint=true, so the read-only safety profile is established. The description adds the ID-scoped nature of the lookup but does not mention not-found behavior or response shape, which is acceptable for a simple read but adds only minimal behavioral context.

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?

A single sentence directly communicates the action and the identifying key. There is no filler, and the most important information is front-loaded.

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 lookup with one required parameter, schema coverage, and a clear readonly annotation, the description is nearly complete. The only gap is the absence of an explicit return-value or error-behavior statement, but 'Get' makes the intended result reasonably implicit.

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 covers 100% of the parameter, including its type and description, so the schema already provides the meaning. The description only reinforces 'by its ID' and adds no new parameter details.

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 verb and resource ('Get a tenant') plus the retrieval criterion ('by its ID'). This clearly distinguishes it from list_tenants and from create/update/delete tenant siblings.

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?

'By its ID' signals when this tool should be used: when the caller has a specific tenant_id and needs a single tenant. It does not explicitly name alternatives like list_tenants for enumeration, so the guidance is clear but not exhaustive.

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