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

Annotations already declare destructiveHint=false and idempotentHint=true; the description usefully confirms the non-destructive effect (clip remains in place, renders as a gap) and notes that an edit result is returned. It stops short of saying the edit produces a new timeline_id, which the schema mentions instead.

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?

Two tight sentences with the key behavioral consequence front-loaded; the second sentence delegates return-format detail to the server instructions rather than bloating the definition. 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 values need no explanation, but for a mutation tool with two undocumented parameters and no usage guidance the definition leaves real gaps an agent must resolve from the schema alone.

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 only 50%: preview and timeline_id are documented in the schema, while clip_id and enabled are bare. The description only obliquely implies the meaning of enabled=false through 'a disabled clip'; it says nothing about what enabled=true does, what clip_id accepts, or format expectations, so the coverage gap is not compensated.

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 name and title carry the verb (enable/disable), and the description adds the crucial semantic distinction: a disabled clip is not removed but 'stays on the timeline but renders as a gap.' That implicitly separates it from clip.remove, though no sibling is named explicitly.

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?

Usage is only implied — the 'stays on the timeline' framing hints you should pick this over clip.remove when you want to preserve the clip, but there is no explicit when-to-use, no prerequisite, and no mention of the alternative by name.

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