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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile, so the bar is lower. The description adds the return format (palette, fonts, components, image URLs). Behavioral details like token trimming and the fold-by-fold autopsy live in the detail/maxTokens schema descriptions, not the main description. No contradiction with annotations, but the description adds only modest behavioral context beyond the safety flags.

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?

A single efficient sentence that front-loads the verb and resource, then states the return payload. Zero filler, every clause earns its place. The description is appropriately brief given the schema carries the parameter documentation.

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 15 parameters and no output schema, the description carries more burden than it currently handles. It does state what is returned, and the schema descriptions compensate for filter semantics. However, it does not explain how multiple filters combine (AND vs OR semantics), nor does it route to the correct sibling. The schema is rich enough that this is adequate but not complete for a search tool of this complexity.

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 93%, so the baseline is 3 even though the description itself adds no parameter-specific meaning. The schema descriptions are individually rich (e.g., paperBand notes it is more reliable than mode, maxTokens explains trimming rules). The description adds the return-format context but nothing about parameter semantics, which is acceptable given the high schema coverage.

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 states a specific verb ('Search') and resource ('archive of real website screenshots'), and names the return content (palette, fonts, components, image URLs). The purpose is clear, but it does not differentiate from similar siblings like find_by_color, find_components, and find_similar, which are also search-like operations. The return format hint partially disambiguates but leaves room for confusion.

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 gives no guidance on when to use this tool versus the many siblings (find_by_color, find_components, find_similar, recommend, get_screen). No exclusions or alternative routing is provided. The rich schema descriptions hint at filter semantics but the description itself offers zero usage direction, which is a notable gap for a tool with 14 search-like siblings.

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