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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered without prose. The description adds real behavioral context beyond that: it discloses the plan-gating rule (free accounts are restricted to gpt-6-luna, starter and above may pick any listed model) and, since no output schema exists, it also characterizes the returned fields.

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 dense but well-formed sentence that front-loads the subject ('Models that can be set per agent') and then enumerates the returned attributes. Every clause carries information; there is no filler or repetition of the title.

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-only listing tool with no output schema, the description covers the essential ground: what is listed, what each entry carries, and the plan-based restriction that affects interpretation. It stops short of describing the response shape (array vs. keyed object) or ordering, which is a minor gap rather than a blocker.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; baseline is 4. No misleading parameter hints are present.

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 identifies the resource precisely as the models that can be assigned per agent and enumerates the per-model attributes returned (rates, typical points of a live call, applicability, `min_plan`), which is well beyond restating the name. It lacks an explicit verb (the listing action is implied by the tool name), but no agent would confuse this with any sibling such as `list_autopilots` or `get_account`.

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?

Usage is only implied: the mention of `min_plan` and the free-vs-paid model availability signals that this is consulted when choosing or configuring an agent's model. There is no explicit when-to-use statement, no statement of prerequisites or ordering relative to create/update tools, and no exclusions.

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