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

With no annotations, the description does add genuine behavioral context: browser processing, higher credit cost than Document/Image/Scanner workspaces, welcome-credit limits, and Day Pass exclusion. It still omits how the input video is supplied, whether the original is preserved beyond the phrase 'save a copy,' and what the output delivery looks like.

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 functional sentence is front-loaded well, but the remainder is a long pricing/plan paragraph repeated from workspace-level boilerplate, ending in a link to mioffice.ai/pricing. That text does not help an agent invoke this specific tool and bloats the definition.

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 zero-parameter, no-output-schema workspace tool, it covers the result (square MP4) and cost/plan constraints. It remains incomplete on input mechanics and whether processing is synchronous or async, which matters for a video operation.

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?

There are zero parameters and schema coverage is 100%, so the baseline is 4. The description adds no parameter detail, but none is needed.

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 opening states a specific verb and resource plus a precise output spec: a 1080 × 1080 square video with a centered crop. That distinguishes it operationally from generic resize or reels/shorts/tiktok siblings, though it never names an alternative explicitly.

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?

Provides no when-to-use versus when-not guidance. 'Check the framing, keep MP4 selected, and save a copy for your next post' is a UI instruction, not routing logic; an agent gets no criteria for choosing this over mio_video_resize, mio_video_crop, or mio_video_resize_reels.

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