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

The annotations already establish this as a safe, idempotent, read-only overview. The description adds useful behavioral context by noting that it lists catalogues with item counts and the age of the knowledge snapshot, which tells the agent how fresh the information is likely to be.

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?

It is front-loaded with 'START HERE' and gives the key contents in two efficient sentences. Every clause adds information about what the overview covers or how it helps choose the next tool.

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 parameterless, read-only orientation tool with no output schema, the description is complete enough: it explains the topics covered, the catalogue/snapshot information included, and its role as a starting point for selecting subsequent tools.

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?

There are zero parameters, so the baseline is 4. The description does not need to explain any input semantics, and the empty schema is consistent with a parameterless overview tool.

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 purpose: it is the onboarding/overview tool explaining how the video editor and `video_project` document work, including schema shape, lanes, clips vs transitions, library id references, and next-tool guidance. The phrase 'START HERE' makes its role distinct from action-oriented siblings like `create_video` or `list_videos`.

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 tells the agent to start here and says it will indicate which tool to call next, giving clear usage context. It does not enumerate when not to use it or name alternative overview/catalogue tools directly, which keeps it short of fully explicit alternative guidance.

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