from_resource

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

No annotations provided, so the description carries full responsibility. It discloses that this is a vision (Gemini) operation on a URL, implicitly indicating it is read-only in nature. However, it doesn't mention behavior around the compact parameter (history compaction/reconnection — a notable side effect), error handling for malformed URLs or unsupported media types, rate limits, or what happens on unsupported resource types, despite the output schema existing.

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?

Extremely concise — a single sentence that defers to the canonical tool. Front-loaded and efficient with zero wasted words. Given that it's an alias, brevity is appropriate. Loses a point because it relies entirely on the alias target; for a self-contained description it is too minimal.

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?

As an alias for a tool with 4 parameters (3 required), an output schema, a media type enum, and many sibling variants (plural vs singular, vision vs non-vision), the description is too sparse. It names only vision_from_resource while the plural and file-based siblings exist. While the output schema mitigates return-value explanation needs, the description does not explain how this differs from vision_from_file, from_resource, or the plural variants.

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 100%, with all four parameters documented in the schema itself, so baseline is 3. The description itself adds no parameter detail beyond pointing to vision_from_resource. The compact parameter's behavior (compacting history, reconnecting) is documented only in schema, not description. Adequate given the alias's extreme brevity.

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 clearly identifies it as an alias for vision_from_resource and states it describes a URL using Gemini. Purpose is clear (verb 'describe' + resource 'URL' + tool 'Gemini'), though it doesn't distinguish from the vision_from_resources plural sibling or the from_resource non-vision variant, instead deferring entirely to the aliased tool.

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 explicit guidance on when to use this alias versus vision_from_resource, vision_from_resources, or from_resource. The 'alias for' framing implies users should normally call the canonical tool, but there's no exclusions, no alternatives named beyond the single alias target, and no context about when this vs siblings is preferable. For an agent with many sibling tools, this is a gap.

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