media_extract_thumbnail

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

No annotations are present, so the description carries the full burden. It discloses the core behavior (extracting a thumbnail) and parameter purposes, but lacks details like output format, file creation behavior, error conditions, or time/width constraints. Moderate transparency.

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 concise (one sentence plus a list), front-loaded with the primary action. The Args section is structured but could be integrated more naturally. No wasted words.

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?

An output schema exists, so return value explanation is unnecessary. The description covers all four parameters briefly. However, it lacks details on output format, behavior for invalid inputs, or auto-generated paths. Slightly incomplete for a 4-parameter tool with no annotation context.

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 0%, so the description must compensate. The Args section explains each parameter's purpose (path, time, output_path, width), adding meaning beyond the schema's names/types. However, it omits constraints (e.g., time >= 0, width > 0) and the default output_path behavior. Adequate but not thorough.

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 tool extracts a frame thumbnail from video at a specific time. The verb 'Extract' and resource 'frame thumbnail' are specific, and the sibling 'media_extract_thumbnails' (plural) suggests a batch variant, making this singular tool distinct.

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 guidance on when to use this tool versus alternatives like 'media_extract_thumbnails' or other media tools. No context about prerequisites (e.g., video accessibility, duration) or when not to use.

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