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

The annotations already declare readOnlyHint=true, so the safe, read-only nature is covered. The description adds minor context by listing what is inspected, which hints at output scope, but it does not disclose limitations such as file size constraints, runtime, or what happens with unsupported codecs. Given the annotation coverage, a 3 is appropriate.

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 a single, efficient sentence followed by a category tag. It is front-loaded with the purpose and the properties list is compact. It slightly duplicates the annotation title ('Video Inspector'), but there is no fluff or excessive verbiage.

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 single-parameter, read-only inspection tool, the description covers the essential information: what it inspects (the file) and what it reports. With no output schema, the property list is helpful. However, it does not explicitly describe the return structure or format, which would make it fully complete.

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 schema describes the file parameter with format: 'binary' and enumerates supported formats, so schema coverage is 100%. The description does not add meaning beyond that; the parameter is self-explanatory. Baseline 3 is correct because the schema does the heavy lifting.

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 uses a specific verb ('Inspect'), a clear resource ('a video'), and enumerates exact data points (duration, resolution, frame rate, codec, audio tracks, bitrate). This makes it easy for an agent to distinguish it from broad siblings like analyze_file or analyze_metadata, and from analyze_audio, without opening schemas.

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 explicit guidance on when to use this tool versus alternatives. The category tag and the video-specific properties imply usage for video inspection, but there are no exclusions or pointer to siblings like analyze_audio or analyze_metadata. The agent must infer the appropriate use case from the tool name and sibling list.

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