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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the basic safety profile is covered. The description adds useful behavioral constraints: 'Requires a query of at least two characters' and 'returns at most 10 results,' which go beyond annotations. It does not disclose rate limits or coverage details, but the added constraints earn a 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?

Two sentences with no wasted words. The first sentence states the core function and scope; the second provides the key constraints. All information is front-loaded, making it easy for an agent to parse quickly.

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 this is a simple search tool with an output schema, the description covers the essential constraints (minimum query, result limit) and the scope ('covered universe'). The optional token authentication is documented in the schema. Nothing critical for correct invocation is missing.

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 description coverage is 100%, so the baseline is 3. The description essentially repeats what the query schema already states (company name or ticker, at least 2 characters). The agent_token parameter is not mentioned in the description, but the schema already fully documents it. No additional parameter meaning is added 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?

The description clearly states a specific verb and resource: 'search Velarion's covered universe by company name or ticker.' It distinguishes itself by emphasizing the free-plan limitation and basic search scope. However, it does not explicitly contrast with any sibling tools, so it falls just short of a 5.

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 implies when to use it: when you need a free, basic company search by name or ticker. It provides operational constraints (minimum query length, maximum result count) but does not mention alternatives or explicitly state when not to use it. This is clear context but no exclusions or routing.

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