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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavioral facts: results are scoped to the calling API key (no cross-key visibility), returned newest first, and an API key is required. It omits what happens at the limit boundary and whether any total count is returned.

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 short sentences with zero filler, and the most important facts (scope and ordering) are front-loaded before the auth prerequisite. Nothing is repeated from the title or schema.

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?

For a simple read-only listing tool with fully described parameters and safety annotations, the description covers scope, ordering, and auth adequately. The remaining gap is that with no output schema, an agent learns nothing about the shape of returned video objects or pagination beyond the limit parameter.

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%, with both limit and status fully documented including enum values and bounds, so the schema does the heavy lifting and baseline 3 applies. The description adds no extra semantics for the filters — it does not say, for example, how status filtering interacts with the newest-first ordering.

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 the videos") plus the scope ("belonging to the calling API key") and default ordering ("newest first"). It does not explicitly contrast with the siblings generate_video or get_video_status, though those are distinct enough operations that confusion is unlikely.

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?

Usage is only implied by the name and verb — an agent can infer this is the enumeration tool versus generate_video (create) and get_video_status (single-item status). There is no explicit when-to-use/when-not-to-use statement or guidance on choosing between listing and polling status.

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