Perplexity Help

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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false. The description adds genuinely new behavioral facts beyond them: it is free and makes no API call, which matters for an agent deciding whether to invoke it.

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 sentence that front-loads the default action and the routing flow, then lists modes and ends on the cost/behavior note. No padding.

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 an output schema present, return details need not be described. The description covers modes, the default entry point, the zero-required-parameter nature, and the cost/API behavior, which is complete for a 2-param help 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?

Schema coverage is 100% with both parameters fully documented (including the default action=index and the name-per-mode relationship), so the schema carries the load and baseline 3 applies. The description adds the topic enumeration (routing, costs, citations, errors, projects), which is a small increment over the schema.

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 states this is the server's help/routing entry point ('How to use this server... picks the right tool'), which cleanly separates it from the ten sibling query tools. It lacks a crisp verb+resource framing, but for a meta-help tool the purpose is unambiguous.

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?

It gives an explicit sequenced workflow: start with action=index, then switch to tool/topic with a name. It does not name when NOT to use it (e.g., skip straight to perplexity_ask if the tool is already known), but the 'picks the right tool' framing implies that.

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