Network Thumbnail

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

Annotations are absent, so the description carries the full burden of behavioral disclosure. Disclosing the HTTP GET method hints at a read-only operation with no side effects, which is useful. However, it omits the response format (binary, base64, URL), error behavior for missing files, and whether any caching is involved.

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 a single front-loaded sentence that efficiently states its purpose and API endpoint without wasted words. The parenthetical endpoint is a useful, compact addition. It earns a slight deduction only because the sentence could have been expanded with usage context without losing its tight structure.

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 single-parameter, schema-documented read-only operation with no output schema, the description is mostly complete for the core fetch behavior. However, the lack of return-type specification (binary image data vs. URL vs. base64) creates a gap, given there is no output schema or annotation to fill it.

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?

The schema documents the single `file` parameter as 'Network thumbnail path.' with 100% coverage, which meets the baseline. The description adds minimal value by including the endpoint `?file=...` query string, confirming how the parameter is transmitted, but adds no extra meaning beyond what the schema provides.

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 uses a specific verb+resource structure ('Get a thumbnail for an extra-network item') and reinforces it with the HTTP endpoint. This makes the purpose unambiguous and distinguishes it from unrelated sibling tools. However, it does not differentiate from similar-looking thumbnail tools like sdnext_browser_thumb.

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?

No guidance is given on when to use this tool versus alternatives. The description is purely declarative with the endpoint and offers no explanation of the 'extra-network item' concept, nor does it mention when a user would prefer this over the similar sdnext_browser_thumb tool. No exclusions or alternatives are cited.

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