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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds useful context beyond that: the exact content returned and the authorization requirement ('needs the user's Cotlet API key with access to this app').

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 lead fragment and the following sentence restate the same field list ('One tenant: contacts, lease dates, rent and balance' then 'Returns one tenant with contacts, lease start and end, monthly rent and current balance'), which is minor but real redundancy. The usage and auth notes are otherwise front-loaded and compact.

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 carries the burden of explaining the return payload, and it does so by naming the exposed fields. It covers purpose, return content, auth, and a usage trigger, leaving only pagination/error behavior unaddressed.

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 is a single parameter with 100% schema coverage; the schema documents tenant_id and its source ('from list_tenants'). The description does not add format or sourcing detail beyond what the schema states, so the baseline of 3 is correct.

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 ('one tenant') and enumerates the returned facets (contacts, lease dates, rent, balance), so an agent knows exactly what it retrieves. It does not name or contrast with list_tenants or get_tenant_ledger, so sibling differentiation is left to inference.

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?

Provides a clear usage context – 'use it before a call or a text to see the whole picture for one unit' – which tells the agent when this tool is the right choice. It does not state when not to use it or point to a specific alternative, so it stops short of a 5.

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