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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is fully covered. The description adds one piece of real behavioral context — that the returned props schema is editable — but says nothing about ordering, empty-project behavior, or how large the props payload is. With annotations doing the heavy lifting a 3 is right.

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?

A single dense sentence with zero filler, front-loading the verb and resource and then packing the return fields inline. Nothing could be removed without losing information.

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 field enumeration does the job an output schema would, and the annotations cover safety. Slightly short of 5 because it does not describe the shape of the props schema or note that the list may be empty for a project with no compositions.

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 100%: token (the session token from connect) and projectId (from get_projects) are both documented in the schema. The description adds no parameter guidance of its own, so the baseline 3 applies.

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?

States a specific verb (Lists) and resource (the project's motion compositions), then enumerates exactly what comes back: id, mediaRef, name, size, fps, duration, editable props schema. That field list also implicitly separates it from get_motion_composition, which returns a single composition.

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 routes downstream usage by tagging mediaRef as "(for add_clips)", which tells the agent why it would call this before adding clips. It stops short of naming alternatives such as get_motion_composition for a single item or update_motion_composition for edits, so context is clear but exclusions are absent.

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