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

Annotations already indicate readOnlyHint=false and destructiveHint=true. The parameter descriptions add useful behavioral detail, such as 'Omit to keep the current...' and 'send to replace it,' making the partial-update semantics clear. No contradiction exists between the description and 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?

The description is short, but the 'Guidance: Update one CMS video item by video id. | context: id' sentence is redundant with the opening line. Parameter descriptions are concise and well-structured, so the overall definition is still efficient.

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?

The tool is well-covered by parameter-level descriptions, and the id description explains where to obtain existing ids. However, it does not describe return values or failure behavior, and there is no explicit note about how this tool relates to sibling video tools (e.g., paragraphs). Given the absence of an output schema and the richness of parameter docs, this is only a minor gap.

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?

Every parameter, including nested fields under meta, has a description that adds meaning beyond the schema. Details like 'Do not send scheduled', 'Requires status="stock" when provided', and 'Set an explicit iframe width and height' provide actionable guidance for correct usage.

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 action ('Update') and the resource ('video item'), and identifies the target by video id. It is easily distinguishable from sibling tools like cms_update_video_paragraph, cms_create_video, and cms_delete_video.

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 provides no explicit guidance on when to use this tool versus alternatives. It does not mention that creation should use cms_create_video, deletion should use cms_delete_video, or that paragraph edits should use cms_update_video_paragraph. The 'Guidance' line merely restates the tool's function.

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