pplx_usage

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

With no annotations provided, the description carries the full burden of disclosing behavior. It explains that the tool checks current usage, shows remaining quotas (weekly, monthly), and supports an optional refresh parameter to ignore cache. This is sufficient for a read-only informational tool, though it could mention the absence of side effects explicitly.

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?

The description is concise and well-structured. It opens with a clear one-line summary, follows with usage guidance, then details the tool's scope and the parameter. Every sentence adds value, with no redundancy or fluff.

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 simple tool with one parameter and no complex output, the description is largely sufficient. An output schema exists (not shown) which can cover return values, so the description need not dwell on them. It covers purpose, usage, and parameter semantics adequately.

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 only parameter 'refresh' is fully explained in the description: 'Force refresh from Perplexity (ignores cache). Default False.' Since schema description coverage is 0%, the description compensates entirely by providing meaning beyond the raw 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 explicitly states it checks Perplexity usage limits and remaining quotas, clearly distinguishing it from sibling tools like pplx_ask and pplx_query which focus on making queries. The verb 'check' and resource 'usage' are specific and 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?

The description includes a direct instruction: 'CALL THIS AT THE START OF EVERY SESSION before making any queries.' It also explains how to use the results to decide whether to conserve Pro quota, providing practical guidance on when to use the tool versus alternatives.

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