extract_frame

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

No annotations are present, so the description carries full responsibility for behavioral disclosure. It mentions the PNG output but omits important behavior such as the unit of 'time', how the output is returned or saved, and what happens for invalid or out-of-range frame times.

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, compact sentence with no filler, and it front-loads the key action and output format. Brevity is good, but it omits necessary parameter and usage details that could have been added without much bloat.

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 tool with no annotations, no output schema, and zero parameter documentation, this description is too sparse. An agent is left without time units, input_video format expectations, output delivery details, or error behavior, so it cannot reliably invoke the tool in non-obvious 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 description coverage is 0%, and the description adds little explicit parameter meaning. It implies that 'time' selects the frame and that 'input_video' names the source, but it does not specify units, accepted formats, or path conventions beyond the raw schema.

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 operation ('Extract'), the target ('a specific video frame'), and the result format ('PNG'). It distinguishes the tool from siblings like freeze_frame or create_thumbnail by specifying a still-frame PNG output, though it does not explicitly contrast them.

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 guidance on when to use this tool instead of related siblings such as freeze_frame or create_thumbnail. No use cases, exclusions, or alternative recommendations are provided, leaving the agent to infer usage from the name alone.

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