extract_frame

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

No annotations are provided, so the description must carry behavioral context. It discloses that the tool creates/saves an image file and extracts content from a video, which communicates the primary side effect. It does not detail output file naming or overwrite behavior, but the core behavior is transparent enough.

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 compact and front-loaded with the main action, followed by a short use-case statement and parameter notes. Every sentence serves a purpose and no filler is present.

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 relatively simple extraction tool, the description covers purpose, parameter semantics, and the typical scenario. It could be more complete by mentioning where the image is saved or what the output schema contains, but it is still sufficient for an agent to select and invoke correctly.

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%, and the description compensates by explaining path as relative to the workspace and time as expressed in seconds. image_format only restates the enum values from the schema, so it adds some but not exceptional value.

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 states a specific verb and resource: extracts a single frame from the video at a given instant and saves it as an image. It also hints at the intended use case ('before cutting'), which helps distinguish it from sibling tools like cut_video or detect_scenes.

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?

It provides clear context by saying this is useful for visually inspecting content before cutting. However, it does not explicitly mention when not to use it or name alternative sibling tools.

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