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

Annotations already declare destructiveHint=true and idempotentHint=true; the description adds genuinely new context beyond them: the owner-only authorization constraint, the fact that the recipient gains edit/upload/run/render rights, and that unshare revokes them. It does not spell out irreversibility or error behavior, keeping it at a 4.

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?

Front-loads what the tool does, then the effect on the recipient, then authorization, then the action enum and the guardrail. Every sentence is informative, though the enumeration of granted capabilities is slightly verbose.

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?

No output schema exists, and the description partly covers the return by saying the list action shows 'who has it'. Combined with the owner-only rule and the effect-of-share explanation, an agent has enough to invoke it correctly, with minor gaps around the exact list payload and unshare edge cases.

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 67%; the schema already explains email and action in detail, and the description largely restates the email requirement. The required project_id has no description in either place, so the description does not compensate for that 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?

States a specific verb set (share/unshare/list) on a specific resource (Switch Editor project collaborators), and enumerates exactly what sharing confers (media, chat history, renders, edit/upload/run/render rights). An agent can distinguish it from delete_editor_project and list_editor_projects without opening a schema.

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?

Gives an explicit selection rule for the share action ('Share only when the person named the email and said to share') and states the default action (list). It does not name a sibling alternative or a when-not-to-use case beyond that, so it falls short of a full 5.

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