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

The description directly contradicts the annotations: it states 'Idempotent — adding a user who is already a member is a no-op,' while the annotations declare idempotentHint=false. Although it adds useful permission and scope details, the idempotency contradiction is a serious inconsistency.

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?

Three compact sentences, front-loaded with the core action, followed by parameter source, idempotency, and permissions. Every sentence is relevant and there is no wasted text.

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?

The description covers permissions, API-key scope, parameter source, and intended behavior, which is useful for a mutation tool with no output schema. However, the incorrect idempotency claim undermines completeness, and return behavior is not described.

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%, so parameter meanings are already documented. The description adds marginal value by indicating that userUuid should come from pm_list_workspace_members, but does not explain the other parameters beyond schema coverage.

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 verb and resource: 'Add a single user to a team.' It also points to the UUID source and distinguishes the operation clearly from sibling tools like pm_remove_team_member and pm_list_workspace_members.

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 gives clear usage context: pass the user UUID from pm_list_workspace_members, requires MANAGE_TEAMS, and needs API-key scope teams:write. It does not explicitly name when not to use this tool, but the requirements and source are well specified.

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