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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description adds real behavioral value beyond that: the access-level downgrade rule (an invited editor appears as viewer when the editor cap is hit or the owner is on the Free plan) prevents an agent from misreporting permissions, and the enumerated return fields describe what a call yields.

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 sentences, front-loaded with the purpose before the field enumeration and the access caveat. The field list is long but functional since there is no output schema; the only minor slack is that the access-downgrade sentence is dense enough to require a second read.

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 and no parameters, the description carries the burden of explaining results, and it does so by naming every returned field plus the access-level caveat. It omits ordering/pagination or result-count behavior, which is the main remaining gap for a list tool.

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 the baseline is 4. The description correctly offers no parameter guidance and instead spends its words on output semantics, which is the right allocation here.

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 ('Lists the toro4n models') plus scope ('the user has online, including models shared with them'). That scope cleanly separates it from get_model (single model) and list_versions (version history) without needing to open 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?

Scope is implied by 'models the user has online, including models shared with them', which tells the agent this is a per-user inventory rather than a global listing. However, it never names an alternative or states when to prefer get_model or list_versions, so the routing decision is left to inference.

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