image_search

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

With no annotations provided, the description carries the full burden. It mentions the source and scale but does not disclose behaviors like rate limits, authentication requirements, or whether results are cached. The description is honest but not richly transparent.

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 that are direct and focused, front-loading the key value proposition (search 1.8B+ images) and context (Arquivo.pt historical web). No unnecessary words.

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 the tool's complexity (11 parameters, no output schema), the description covers the search scope and filters adequately. However, it does not describe the return format (e.g., URLs, metadata) or pagination behavior, which could be inferred from the schema but not explicitly stated.

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 high (91%), so baseline is 3. The description adds general context about historical images but does not explain parameters beyond what the schema already provides. For example, 'safe_search' and 'more' are well-documented in 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 the tool searches archived images on Arquivo.pt, specifying the scale (1.8B+), the domain (Portuguese web), and types of images (historical photos, logos, graphics). It distinguishes itself from sibling tools like 'search' (likely text) and 'extract_text'.

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 usage for finding historical images from the Portuguese web, but does not explicitly contrast with siblings like 'search' for text queries or 'get_screenshot' for current captures. No exclusions or alternative tool references are provided.

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