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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and a closed-world scope, so the safety profile is fully covered without the description. The description adds a workflow hint (call before mutating an inbox) but says nothing about result size, ordering, or pagination limits for an account-wide list.

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 tight sentences: the capability first, then the invocation conditions. No filler, no repetition of the title, and the most decision-relevant content 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?

There is no output schema, so the description should carry the return story; 'with their settings' plus the enumerated field list in the schema gives an adequate picture of what comes back. Missing pagination/scale behavior keeps it from being fully complete, but for a simple read-only no-required-param tool this is sufficient.

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% for the single optional 'fields' parameter, including a clear enumeration of selectable fields, so the schema does the heavy lifting. The description never mentions the field-selection capability, adding no meaning beyond the schema – the baseline of 3 applies.

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 and resource ('List the inboxes (channels) of this account') and clarifies the scope with 'with their settings', adding the useful synonym 'channels'. It does not explicitly differentiate itself from the sibling get_inbox (singular), so the agent must infer plural-vs-single on its own.

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 concrete call conditions: before changing an inbox, or when the admin refers to a channel, WhatsApp number, website widget or inbox by name. That is real when-to-use guidance tied to observable triggers. It stops short of naming alternatives (e.g., use get_inbox when you already have an id) or any when-not conditions.

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