add_project_user

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

No annotations are provided, so the description bears full responsibility for behavioral disclosure. It only states that the tool returns an empty dict on success, but fails to mention idempotency, side effects (e.g., if user is already linked), required permissions, or whether the operation is reversible. For a mutation tool, this is insufficient.

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?

The description is extremely concise, using a clear Args/Returns format with no extraneous words. It covers the essential information in a compact, easy-to-read manner.

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 provides the return type (empty dict) and parameter roles. However, it omits important contextual details for a mutation tool, such as idempotency, error states (e.g., duplicate link), and dependencies. Given that an output schema exists and the tool is simple, the description is minimally adequate but not fully complete.

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?

Although schema coverage is 0%, the description explains the semantics of all three parameters: project_id, user_id, and role, including the allowed values for role (owner, manager, task_runner, guest). This adds meaningful context beyond the input 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 clearly states the action ('Link a user to a project with a role') and identifies the resources (user, project) and the key attribute (role). It distinguishes itself from sibling tools like remove_project_user and update_project_user by focusing on adding a user.

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 provides no guidance on when to use this tool versus alternatives such as update_project_user or remove_project_user. It lacks context on prerequisites, typical scenarios, or why one would choose this over other related tools.

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