add_parent

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

With no annotations, the description carries the full burden. It discloses a key behavioral trait: 'The new user id is not returned — call list_students or the parent roster afterward.' It also states the invariant that a parent is always created attached to at least one student. This is valuable context beyond what the schema provides, though it does not discuss failure modes 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?

The description is concise and well-structured: a clear purpose sentence, a requirement note, a behavioral note, and a clean Args list. Every sentence earns its place, and the critical information is front-loaded. No fluff 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?

Given that an output schema exists (though not shown), the description need not explain return values; it even goes beyond by stating what is NOT returned. It covers required permissions, the attachment constraint, and the follow-up action. It lacks error cases or idempotency details, but for a create operation with clear inputs, this is sufficiently 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?

Schema coverage is 0%, so the description must compensate. It lists each parameter with a brief description, notably clarifying that student_id is from list_students and that email/phone are optional. This adds meaning beyond the bare schema names and default nulls, though it could be more detailed about format constraints (e.g., phone format).

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: 'Create a guardian/parent and link them to a student.' This specific verb+resource distinguishes it from siblings like edit_parent, link_guardian_to_student, and invite_parent, which handle different aspects of parent management.

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 clear context for usage: it requires PS_ENABLE_WRITES, always attaches to a student, and instructs to get student_id from list_students. It does not explicitly mention when to use an alternative tool (e.g., link_guardian_to_student for existing parents), but the conditions are implied strongly enough for an agent to infer the right usage scenario.

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