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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is covered. The description adds non-obvious behaviors the annotations cannot: alias/former-name matching and the exact return shape ({ name, slug }). Minor gaps remain (no mention of the limit ceiling behavior here), keeping it at 4.

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?

Front-loads the purpose and the slug-resolution rationale, then layers fallback guidance and return shape in a logical order. Slightly wasteful: the closing 'REQUIRED arguments: searchText' duplicates the schema's required field.

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?

No output schema exists, and the description compensates by stating the exact return type (array of { name, slug }) plus empty-result behavior. For a two-parameter lookup tool, everything needed to call it correctly is present.

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%, and the schema already describes searchText as accepting current or former names, so the description largely repeats structured data. It does reinforce that searchText is required, but adds no syntax or format detail beyond 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?

States a specific verb and resource ('Search companies') plus the concrete output ('Levels.fyi slugs'), and distinguishes itself from search-all by naming the fallback sibling. An agent can tell immediately what this returns and why slugs matter.

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?

Explicitly instructs 'Use this FIRST' as the resolution step before benchmark tools, and states the fallback condition ('If this returns no matches, fall back to search-all'). Both when-to-use and the alternative path are spelled out.

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