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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds real behavioral context beyond them: results are 'verified by downloading' from the company's own site (implying a live network fetch, not a stale cache) and the batch cap of 'up to 5 per call.' It does not discuss failure modes for domains with no discoverable logo.

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?

Three tight sentences with no filler; the core verb+resource leads, followed by the output payload, then the usage trigger and input constraints. The colon-separated field list is dense but each item is informative rather than decorative.

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 one required parameter, 100% schema coverage, no nested objects and no output schema, this description is close to complete: it enumerates the return fields (standing in for the missing output schema) and states the batch limit. Only the behavior when no logo is found is unaddressed.

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 restates accepted input forms ('domains, URLs or work emails; up to 5 per call') but adds no format syntax, normalization behavior, or error handling beyond what the schema already documents with examples.

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 ('Find') and resource ('a company's real logo and square icon') and goes further by enumerating the returned fields (logo URL, icon URL, format, size, transparency, brand name, brand colour). An agent knows exactly what it gets back without opening anything else. No siblings exist to confuse it with.

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 states the trigger condition: 'Use when you need a company's logo image or brand colour.' That is clear context for invocation. It stops short of exclusions or alternatives (e.g., what to use for non-company logos), but there are no sibling tools to route against.

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