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

With no annotations, the description carries the full disclosure burden. It does disclose the matching mechanism (CLIP visual similarity plus directory weighting), that image_url must be publicly reachable, and the return shape, but says nothing about permissions, rate limits, cost, or that coverage is limited to US marks (despite a country parameter).

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-loads the core capability (以图搜图) before the use case, then lists parameters and return values compactly. It is appropriately sized for the tool's complexity, though the parameter/return block reads as a dense run-on rather than cleanly separated lines.

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?

No output schema exists, so describing the return shape ({count, results:[{mark, visual_similarity, risk_level, applicant, legal_status}]}) is genuinely necessary and provided. Combined with parameter notes and the stated use case, an agent has enough to invoke the tool correctly, with only country the gap.

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 0%, so the description must compensate, and it does for image_url (public URL, PNG/JPG), nice_class (optional Nice classification), and limit (default 10). The country parameter is never mentioned, leaving one of four parameters undocumented in both schema and description.

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 and resource: reverse image search (以图搜图) returning visually similar US graphic trademarks. The image-based retrieval distinguishes it implicitly from the sibling trademark_text_search, and the seller use case (checking whether a logo collides with a registered graphic mark) is explicit.

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?

Clearly states the intended scenario: sellers checking their own Logo/pattern against registered graphic trademarks. It gives a concrete context but names no alternative sibling or condition under which a different search (e.g. trademark_text_search) would be preferred, so it does not reach explicit when/when-not routing.

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