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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description adds genuine value beyond that by disclosing the returned artifacts and the intended pre-execution workflow; it does not cover failure behavior for an invalid slug, which keeps it from a 5.

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?

One sentence, zero filler, front-loaded with the returned artifacts and ending on the reason to call it. Every clause earns its place.

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 present, the description correctly compensates by naming what the response contains (input schema, output schema, normalized schema, price, category). Only error/unknown-slug behavior is left unstated, which is a minor gap for a one-parameter read 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?

Single parameter with 100% schema description coverage ('Tool slug from search_tools, e.g. brasilapi.cnpj'), so the schema carries the semantics. The description adds no format or resolution detail beyond what the schema already provides, making 3 the correct baseline.

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 (get/inspect) and resource (a tool's input schema, output_schema, normalized_schema, price, category), enumerating exactly what is returned. An agent can distinguish it from search_tools (discovery) and run_tool (execution) from the text alone.

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?

"before running it, so you can write the parsing code first" gives a clear temporal/conditional use case that implies run_tool as the follow-up action. No explicit exclusions or naming of the alternative tool, so it stops short of a 5.

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