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

The readOnlyHint=true annotation already covers the safety profile, so the description only needs to add context. It discloses that no identifier is needed (it is always the current tenant) and what is returned, which is useful. It does not mention auth requirements or what 'settings' entails, but the annotations lower the bar.

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 compact clauses, one carrying the return payload and one carrying the endpoint mapping, with nothing wasted. The key fact (current tenant) 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 zero-parameter read tool with no output schema and annotations covering safety, the description supplies the essential missing piece: what comes back (name, id, settings). Only the unpacked contents of 'settings' are left vague, which is a minor gap.

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?

There are zero parameters, so the baseline is 4. The description correctly implies no input is required by scoping to the 'current' tenant, and the empty schema is consistent with that.

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 (Fetch) and resource (the current tenant) and enumerates the returned fields (name, id, settings). It also pins the exact API endpoint, GET /tenants/self, making the target unambiguous. It doesn't explicitly differentiate from siblings like get_tenant_usage or whoami, but the scope is clear.

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?

No guidance on when to use this versus alternatives such as basis_theory_get_tenant_usage or basis_theory_whoami, both of which also touch the current identity/tenant. An agent gets no signal about choosing among them; the usage is only implied by the name.

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