fetch_product_images

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

With no annotations, the description carries the full burden and does it well. It discloses that the tool scrapes candidate pages, verifies images via HTTP, deduplicates near-identical crops, maintains a TTL disk cache, and returns a status field. It does not cover rate limits or failure modes, but the core behavior is clearly described.

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?

The description is well-structured with bold section headers: summary, usage conditions, example queries, and return fields. It is appropriately sized and front-loaded; every section adds meaningful guidance without verbose filler.

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?

For a web-extraction tool with four parameters and an output schema, the description covers the workflow, return format, and example invocations. It could better disambiguate from the sibling tool get_product_images_tool, but the provided detail is sufficient for an agent to call it correctly.

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 100%, so the baseline is 3. The description adds value with concrete example queries showing how to pass product names, URLs, max_images, and site_filter, which reinforces the schema's documentation without being redundant.

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?

Description clearly states a specific verb and resource: 'Universally extracts verified, high-resolution product photography and official sources across the web.' It also conveys a distinct approach (automatic discovery, HTTP verification, deduplication) that differentiates it from generic scrapers, though it doesn't explicitly name or contrast sibling tools.

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 'USE THIS TOOL WHEN' section explicitly lists the scenarios for using this tool: needing product photos, packshots, visual references, or master CDN assets. It also describes the automatic discovery and verification behavior. It does not state exclusions or alternatives, but the context is clear enough for an agent to select it.

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