add_project_member

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

With no annotations, the description carries the full behavioral burden and delivers little: it doesn't state the permission level required to add members, whether re-adding an existing member is idempotent or errors, whether access is granted immediately, or what happens on failure. 'Add' conveys mutation but nothing about consequences or reversibility.

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?

A single front-loaded sentence with no filler or redundancy. It is appropriately sized for the information it contains, though that information is thin rather than dense.

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 4-parameter write operation with no annotations and no output schema, the definition is under-specified: it says nothing about required permissions, the semantics of the optional expires_at membership window, or error behavior. The schema covers parameter details but the description leaves the mutation's contract largely unexplained.

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 user_id, project_id, access_level and expires_at are already fully documented in the schema, including GitLab access-level values. The description only restates role/access level and adds no syntax or formatting detail 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?

The description names a specific verb ('Add'), resource ('user to a project') and the key payload ('role/access level'), so an agent can distinguish it from update_project_member and remove_project_member at a glance. It stops short of explicitly naming those siblings or the boundary conditions that separate add from update.

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?

There is no when-to-use or when-not guidance. The agent must infer from the verb alone that this creates a membership rather than modifying one, and nothing tells it whether to prefer this over update_project_member for an existing member or what preconditions must hold.

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