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

Annotations already declare this as a non-destructive write with no open-world access, so the safety profile is covered. The description adds genuine behavioral context by noting the video plays when the deck is presented or viewed, but says nothing about what happens if the placeholder already holds content, whether links are validated, or whether the insertion is reversible via deck_undo_turn.

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 sentences, front-loaded with the action and placement target, with every clause carrying information about inputs or runtime effect. The only wasted space is the slightly imprecise parenthetical tool reference, and the trailing playback sentence could be trimmed without much loss.

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 three-parameter write tool with no output schema, the description covers the destination, accepted sources, and the visible effect, which is a solid core. It stops short of explaining slot-overwrite behavior, link validation, or how failures surface, leaving gaps an agent would hit on edge cases.

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 coverage is 100%, so the baseline is 3; the description earns an extra point by enumerating the accepted video hosting providers, which meaningfully narrows the `video` parameter beyond the schema's generic "video link" wording. It adds little for `slide` or `document_id`, which the schema already documents adequately.

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 target ("Puts a video in a slide's <div data-video> place"), which clearly separates it from the image-placement sibling deck_place_image. The only blemish is citing "list_images" as the source tool when the actual sibling is named deck_list_images, which could send an agent looking for a non-existent tool.

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 effectively defines the accepted input domain (an uploaded video shown by the listing tool, or a YouTube/Vimeo/Loom/Instagram/TikTok link), which tells an agent when this tool applies. It gives no explicit when-not guidance or routing to alternatives such as deck_place_image or deck_insert_slide, so the usage boundary is only implied.

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