Perplexity: Models

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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint, so the safety profile is covered. The description does add real value beyond that by naming the returned fields ('routing traits (thinking, writing, reasoning, research, speed) and the gated tiers'), but it never explains what 'gated' means (entitlement-restricted?) or whether listing includes models the account cannot actually call.

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 front-loaded sentence that identifies the resource first and the payload second, with no filler. It is compact but slightly dense in its parenthetical trait list, which crowds the sentence.

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 correctly compensates by summarizing what is returned, and for a zero-argument read-only list tool that is nearly enough. The one missing piece is the distinction from 'perplexity_model' and any clarification of the gated-tier concept.

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 and the baseline of 4 applies. The schema confirms an empty, closed object with additionalProperties=false.

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 gives a specific verb and resource ('List the models this account can select') and even previews the payload shape (routing traits, gated tiers), so the agent knows exactly what the call returns. It does not differentiate itself from the very similar sibling 'perplexity_model', which the agent must infer is the singular counterpart (select/get one model) rather than the enumerator.

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?

There is no when-to-use statement, no prerequisites, and no mention of the near-identical sibling 'perplexity_model'. An agent facing both tools has to guess from names alone which one discovers options and which one chooses or reads the active model.

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