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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is fully covered. The description adds only the credit-cost warning (which concerns video generation, not this read tool) and the default-values pointer; it says nothing about the return format or scope. Modest added value above annotations.

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?

Two compact sentences, with the core purpose front-loaded and the alternative/cost caveat second. No filler, though the credits warning is tangential to this specific tool.

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?

A zero-parameter read-only list tool with annotations covering the safety profile and no output schema; the description adequately states what it returns and routes to get_video_model for detail. Minor gap: it doesn't hint at the shape of the returned model list.

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?

Zero parameters, so per the baseline the schema carries nothing to document and the description is not expected to compensate. Nothing in the text misleads about 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?

States a specific verb and resource ('List available video models and their capabilities'), and the 'video' qualifier implicitly distinguishes it from the list_image_models/list_music_models siblings. It does not explicitly name or contrast those siblings, which keeps it short of 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?

Names the alternative tool (get_video_model) and the condition that selects it ('detailed pricing and the values used when options are omitted'). This is clear routing guidance, though it never states when this list tool is preferred over just calling get_video_model directly.

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