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

Annotations already declare readOnly, non-destructive, closed-world, so the safety profile needs no restating. The description goes beyond them by explaining what each returned flag means operationally ('assigned' = this agent, 'answerable' = Aide can answer, 'replies' = sent vs drafted), which is real behavioral context absent from the annotations. It omits any mention of pagination behavior, though the schema covers that.

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?

One front-loaded sentence starting with the verb and resource, followed by the result shape, with the follow-up action last. The parenthetical channel enumeration is long but earns its place by defining an ambiguous term; no filler sentences.

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 usefully enumerates the returned fields, and the readOnly annotations plus fully documented schema cover the rest. An agent has enough to call it and interpret the response; only pagination and ordering/empty-result behavior are left 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?

Schema coverage is 100% and every parameter (page, agentId, perPage) is documented in the schema, including where agentId comes from. The description adds only that returned ids feed set_inbox_ai, which is workflow rather than parameter semantics. Baseline 3 is appropriate.

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 an AI agent can answer') and immediately disambiguates what a 'channel' is by enumerating the concrete sources (chat widget, support mailboxes, helpdesk, Gmail inboxes). This distinguishes it from sibling listers like list_agents or list_integrations without opening a 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?

The closing line 'Use an id with set_inbox_ai' gives a concrete next-step workflow, signaling this is a discovery step before configuring an inbox. It lacks an explicit when-not or a named alternative among the many list_* siblings, but the context for use is clear.

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