pixabay_search

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

Annotations already cover safety (readOnlyHint, destructiveHint=false, openWorldHint), yet the description still adds real context: it names the official developer API and discloses a content limitation (no music/sound effects) that would otherwise only surface as an empty result set. It omits auth/API-key requirements and rate limits, which keeps it off a 5.

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?

One dense sentence front-loads the verb and resource, then the filter list, then the return shape, with the no-music caveat parenthesized at the end. No sentence is redundant and nothing is buried mid-paragraph.

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 13 parameters and no output schema, the description supplies both the filter vocabulary and the return fields (ids, tags, sizes, previews), which is more than most tools at this complexity. Missing pagination defaults/caps and auth expectations keep it short of complete.

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 only 23%, so the description carries the burden and mostly does: it enumerates orientation, category, colors, min size, editorsChoice, order popular|latest, safesearch, page/perPage, and lang, covering nearly all 13 parameters. Residual gaps are defaults and limits (e.g. max perPage, default page) rather than undocumented parameters.

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?

Specific verb + resource ("Search Pixabay (free licence stock) through the official developer API") with the media types it covers enumerated, so an agent knows this is a discovery tool, not a file fetch. It does not explicitly route against near siblings like pixabay_download or media_import, which is the only thing separating it from a 5.

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 (search first, then presumably download/import), and the parenthetical "The public API has no music or sound effects" is a genuinely useful negative scope. But there is no explicit when-to-use, no named alternative, and no statement that results are metadata only rather than downloadable assets.

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