vision_from_resource

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool 'describes' a resource via Gemini but does not disclose what happens with the resource (fetching, media decoding errors, size limits), whether a prompt modifies behavior, what the return format looks like (though an output schema exists), or how the 'compact' parameter affects behavior (reconnect semantics are unexplained). The description is a bare statement of function without behavioral detail.

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, efficient sentence with no wasted words. It front-loads the primary function clearly. However, given the richness of the tool (four parameters, media types, output schema), the extreme brevity borders on under-specification rather than conciseness.

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?

The tool has an output schema and full parameter coverage, which helps. However, with no annotations and a complex sibling landscape (11 related tools varying by input source and plurality), the description should do more to clarify when the single-URL vision variant is appropriate. The bare 'Describe a URL resource using Gemini' does not cover media-type handling, error behavior, or distinction from non-vision from_resource sibling.

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 description coverage is 100%, so all four parameters already have descriptions. The description adds no parameter-level meaning beyond what the schema provides. Baseline 3 is appropriate. One minor note: the 'compact' parameter's reconnect behavior is opaque even in the schema, and the description does not clarify it, but with full coverage the schema carries the burden.

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 'Describe a URL resource using Gemini' is concise and identifies the core action (describe a resource via URL) and underlying model (Gemini). However, it does not differentiate from siblings like vision_from_file (file vs resource distinction exists in the schema parameter names, but not elaborated in the description) or vision_from_resources (plural variant). The purpose is clear but the scope and distinction from sibling tools is under-specified.

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 provides no guidance on when to use this tool versus alternatives. Siblings include from_resource, from_resources, vision_from_resources, and vision_from_file, which differ in input source (single vs multiple, URL vs file) and whether vision (Gemini multimodal) is used. No exclusions or contextual guidance are given, leaving the agent to infer when the URL-resource form is appropriate.

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