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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and notably openWorldHint=false, so safety and idempotency are covered. The description usefully confirms the closed-world nature by framing this as a fixed registry of 5 named providers plus fallbacks, but adds nothing about freshness, rate limits, or whether the list is live versus static.

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?

Front-loaded single sentence that puts the resource type first and the concrete contents immediately after, with no preamble. The bilingual Korean echo is duplicative for a pure-English reader but appears to be an intentional convention in this toolset.

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 no parameters, no output schema, and full annotation coverage, the description carries the burden of explaining what the agent gets back, and it does so by naming the returned dimensions (availability, free tier, capability). Adequate for a zero-arg registry lookup, though it never says how the fallbacks relate to the five primary providers.

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 tool takes zero parameters, so there is nothing for the description to disambiguate and the schema is trivially complete. Baseline 4 applies; no parameter-related gap exists.

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 resource ('video provider registry') and even enumerates the concrete contents (5 named 2026 providers plus fallbacks, availability, free tier, capability). This is far more specific than a tautology, but it never distinguishes itself from the sibling llm_providers, leaving the agent to infer that this is the video counterpart.

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?

There is no when-to-use or when-not-to-use statement, and no alternative tool is named. The agent must infer from the name alone that this is the discovery step before any video generation call, which is a reasonable but unstated inference.

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