search_sketchfab_models

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

With no annotations provided, the description carries the full burden of disclosing behavior. It states that it returns a formatted list and mentions the default for 'downloadable,' but it does not describe authentication, network behavior, or other side effects. This is adequate but not rich.

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 front-loaded with the main purpose and then lists parameters with definitions. It is reasonably concise, though the parameter list repeats some names and defaults from the schema while adding explanations. Overall, every sentence earns its place.

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 moderate complexity (4 parameters, no output schema, no annotations), the description covers the essential aspects: purpose, all parameters with defaults, and the return type ('formatted list'). It is complete enough for an agent to select and invoke the tool correctly, though it could be slightly more specific about the response format.

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 description coverage is 0%, but the description compensates fully by explaining each parameter's meaning: query is text, categories is a comma-separated optional list, count is a maximum with a default, and downloadable filters to downloadable models. This goes well beyond the schema's type/default information.

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 opens with 'Search for models on Sketchfab with optional filtering,' which is a specific verb+resource combination. It clearly distinguishes this tool from siblings like download_sketchfab_model and search_polyhaven_assets by platform and action.

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 establishes a clear context: use this when you need to search for Sketchfab models. It does not explicitly mention when not to use it or name alternatives, but the platform-specific wording and sibling list make the intended usage obvious.

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