Google Images search

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint=false and destructiveHint=false, so safety is covered. The description goes further with latency ('typically a few seconds'), a hard cap (100 images), billing cost ($0.25/1,000, $0.20 Gold+), and a licence-reuse warning — substantive operational context beyond the annotations.

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-loaded with purpose and returns, then filters, then limits/cost. Every sentence carries information, though the inline enumeration of image types ('photo, clipart, line art, face, animated') is redundant with the schema enum.

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, the description compensates by naming every returned field (full-size URL, width/height, thumbnail, source page URL/title/site). Combined with latency, per-search cap, pricing and licensing notes, an agent has everything needed to call and interpret the 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?

Schema description coverage is 100% and each filter has its own enum documentation, so the schema does the heavy lifting. The description restates the filter dimensions (size, colour, type, time, rights) and partially duplicates the image_type enum values, adding little beyond what is already structured.

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 (Search) and resource (Google Images) and immediately describes the returned artifact, so an agent can distinguish it from siblings like search_google_videos or search_google_shopping. No ambiguity about what the tool does.

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?

Usage is implied by the name and the enumerated filters, but there is no explicit when-to-use framing and no routing away from sibling search tools (e.g. videos, shopping, news). The licence caution is useful but is a post-retrieval note, not selection guidance.

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