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

Annotations already indicate a write operation (readOnlyHint=false). The description adds value by specifying the 'Owner only' constraint, which is critical for correct invocation. It does not detail potential side effects like duplicate handling, but the owner requirement is a meaningful behavioral disclosure.

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?

Two concise sentences, front-loaded with the core action. Every sentence provides distinct information: the action, the owner constraint, and identifier formats. No filler or redundancy.

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?

While the output schema is present (covering return values), the description lacks important context such as error conditions (e.g., if user already a team member), relationship to invitation flow, or required user existence. For a simple tool, this is adequate but not comprehensive.

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 100% and already describes both parameters well. The description only reiterates that user_identifier accepts UUID, email, or handle, which is already in the schema. No additional meaning is added beyond the schema.

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?

Description clearly states the verb 'Add' and resource 'user to a team', making the action unambiguous. It also specifies the owner-only restriction and accepted identifier formats, differentiating it from sibling tools like remove_team_member and list_team_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?

The description implies usage context ('Owner only') but does not explicitly state when to use versus alternatives like invitations or other team management tools. No mention of prerequisites like user existence or team membership status.

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