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

Annotations already declare write and non-idempotent behavior, so the description doesn't need to restate that. It adds genuinely useful context: the operation is a write, and visibility of projects/users depends on role, which is a real constraint an agent won't get from annotations.

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?

Single tight sentence plus a limitation clause. Front-loaded with the action. No wasted words, though the endpoint path is somewhat redundant with the tool name.

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 an 8-parameter mutation tool with no output schema, the description is thin. It covers the safety-relevant limitation (role-based visibility) but leaves parameter semantics, especially the project_ids/projects alias and account_id requirement, unclear.

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 63%, and the description adds no parameter meaning at all. It doesn't clarify project_ids vs projects (the alias), whether user_id can be a list, or what account_id does beyond what the schema already says. For 8 parameters with partial coverage, more clarification is expected.

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 (Assigns) and resource (projects to a user) and gives the endpoint path, making it unambiguous against siblings like list_user_projects or assign_users_to_schedule.

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 implied by the name and endpoint, but there is no explicit when-to-use guidance, no mention of when to prefer list_user_projects or how to remove assignments. It doesn't name any alternative tool.

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