compress_video

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explains the quality/size tradeoff via CRF, which is useful, but it does not disclose potential side effects like overwriting the output path, the lossy nature of re-encoding, or processing time. This is adequate but not thorough.

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 three sentences, front-loaded with the core purpose, and wastes no words. Every sentence contributes either to what the tool does or how to use a key parameter.

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 moderate-complexity tool with no output schema and no annotations, the description covers the main purpose and parameter semantics well. It lacks caveats about overwriting or lossy encoding, but given the tool's straightforward nature and schema for paths, it is reasonably 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?

Schema descriptions cover input_path and output_path (50% coverage). The description adds meaningful semantics for crf, which lacks a schema description, by explaining the quality/size relationship and suggesting a default. It does not elaborate on preset, but the enum values are self-explanatory. The added value on crf compensates for the coverage gap.

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's function: 'Reduce a video file size by re-encoding it with a given quality level (CRF).' It identifies a specific verb, resource, and method, and distinguishes itself from sibling tools like resize_video or convert_format by focusing on quality-based compression.

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 explains when the tool might be used (to reduce file size) and provides CRF value guidance, but it does not explicitly state when to prefer this tool over alternatives or mention any exclusions. It gives implied usage context but lacks clear 'use this instead of X' guidance found in higher-scoring examples.

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