pplx_sonar

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

With no annotations, the description must disclose key behaviors. It only notes usage counters and plan dependence, omitting what the tool actually does (e.g., search, return citations) and any side effects. The reference to 'pplx_usage' is helpful but incomplete.

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 extremely concise (one sentence) and front-loaded with the model name. However, the brevity sacrifices clarity; it is under-specified rather than efficiently complete.

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?

Given the tool has 2 parameters and no annotations, the description fails to cover essential aspects like query behavior, source_focus options, or return format. The output schema exists but is not referenced.

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 schema has 2 parameters with zero description coverage, and the tool description adds no meaning to 'query' or 'source_focus'. An agent cannot infer the expected format or effect of these parameters.

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 tool as 'Perplexity's latest in-house model' but does not state the specific verb or resource (e.g., search, generate, answer). It fails to differentiate from siblings like 'pplx_query' or 'pplx_deep_research', which have clearer purposes.

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?

No guidance is provided on when to use this tool versus alternatives. The description only mentions plan and usage counters, which is not sufficient for an agent to decide between this and other Perplexity tools.

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