understand

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

No annotations are provided, so the description carries full burden. It reveals the core behavior (understanding media with a prompt) and provider differences, but lacks details on rate limits, token consumption, or 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 two sentences with no redundancy. The first sentence is the core purpose, the second adds valuable provider nuance. It is efficiently front-loaded, though slightly more structure (e.g., listing param implications) could improve without bloat.

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 6 parameters, 4 undocumented in both schema and description, and an output schema present but unmentioned, the description fails to provide sufficient context for an agent to confidently invoke the tool. Key details like tier options, model/provider defaults, and return value structure are missing.

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 0%, yet the description only clarifies 'media_urls' (multi-URL) and 'prompt' (with a prompt). Critical parameters like 'tier' (default 'poor'), 'model', 'provider', and 'max_tokens' are unexplained, leaving the agent to guess their meaning.

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 states the verb 'understand' and the resources 'images and/or videos (multi-URL) with a prompt'. It distinguishes from sibling tools like 'generate' by focusing on media understanding. The provider-specific nuance further clarifies purpose.

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 gives explicit guidance on when to use which provider (Gemini for mixed media, OpenAI/Grok for image-only). However, it does not explicitly say when not to use this tool or mention alternatives among siblings beyond the implicit distinction.

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