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

Annotations only mark readOnlyHint=false, destructiveHint=false, idempotentHint=false. The description adds substantial behavior: it preserves existing emphasis_words or picks them from the transcript, never touches cuts/music/sfx, and reports every component it set. It also discloses the return behavior (project identity with result). This is far beyond annotation coverage.

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 dense but every sentence earns its place. It front-loads the critical scoping and one-call nature, then enumerates looks, states constraints, and gives adjustability guidance. No filler or repetition.

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?

With no output schema, the description explains what the result contains (project identity, reported components). It covers all inputs, lists the exact enum values with behavior, notes the immutable scope, and clarifies what the tool does NOT do. An agent has everything needed to call it 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 coverage is 50% (only project_id has a description). The description adds semantic meaning to the 'name' parameter by explaining exactly what each look does (e.g., 'hype' = beast xl captions, vibrant grade, zoom_punch cuts, closing fade). It also reinforces project_id's scope. This compensates well for the schema gap, though it doesn't enumerate parameter syntax explicitly.

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 ('apply') and resource ('look'), and immediately clarifies project scoping. It lists five distinct looks (hype, clean, cinematic, luxury, meme) with concrete effects, making the purpose unmistakable and easily distinguishable from sibling tools like add_stylize or set_color_grade.

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 explicitly states when to use this tool: for a one-call aesthetic composition across captions, grade, transitions, fades, and stylize. It also gives a clear exclusion: 'Never touches cuts, music or sfx — place accents with add_sfx.' This is direct when/when-not guidance with a named alternative.

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