signupgenius_add_group_member

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

Given that annotations only provide readOnlyHint=false (which means the tool writes data), the description goes beyond this by explicitly stating 'Writes data — confirm with the user before invoking.' This adds a caution about user confirmation and clearly indicates a mutation, which is important for an agent to know. It does not contradict the annotations; in fact, it reinforces the write operation.

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 concise and front-loaded with the core purpose. It states the action, target, method, optional fields, and a clear warning in just two sentences. Every sentence adds value, and the structure is efficient.

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 relatively simple mutation tool with 4 parameters (2 required) and no output schema, the description covers the essential aspects: what it does, what it needs, and what side effects to expect. It does not specify return values or error handling, but the low complexity and lack of output schema mean that these are less critical. The explicit write warning adds to completeness.

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?

The schema description coverage is only 25%, and the only parameter with a description is 'emailaddress' (in the schema). Required parameters (groupId, emailaddress) are described by name, but groupId has no description beyond type and constraints. The description adds that first/last name are optional, but does not explain how these parameters are used or any additional semantics, leaving the agent to infer meaning.

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 ('Add a member'), the resource ('SignUpGenius group'), the method (by email address), and notes that first/last name are optional. This distinguishes it from sibling tools like 'list_group_members' or 'get_group_member' which are read-only and require a member ID.

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 (add a member to a group) but does not explicitly state when to use this tool versus alternatives. It also does not mention any prerequisites, such as having the correct groupId or ensuring the email is not already in the group. The explicit warning to confirm with the user is helpful but not a full usage guideline.

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