Send message

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

Annotations already indicate readOnly=false, and the description adds important behavioral detail: the message cannot be unsent, and the agent must confirm recipients and text with the user before calling. It also discloses the exact-match requirement for teacher names, going beyond the structured annotations.

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 sentences with the core action front-loaded and no filler. The phrase 'by subdomain or a student's name' is slightly dense and ambiguous, but every sentence earns its place and the structure is scannable.

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?

With an output schema and annotations available, the description covers the essential invocation details: recipient resolution, optional school handling, and irreversibility. It does not describe error behavior or invalid-recipient handling, but those are not strictly needed for a correct call.

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 0%, so the description must compensate. It does well for recipients (teacher names or IDs from list_teachers, requiring exactly one match), but school is only obliquely covered via 'by subdomain or a student's name,' and text receives no added semantics beyond being the message body. Compensation is partial.

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?

States a specific verb ('Send'), a specific resource ('new EduPage message'), and the recipient scope ('one or more teachers at a school'). This clearly distinguishes it from the sibling read-only tools such as get_messages and list_teachers, so an agent can identify the correct tool from the description alone.

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?

Provides clear usage context: it is the send action from the current account, appropriate for messaging teachers, and it explains how to resolve recipients via list_teachers. It does not explicitly state when not to use it or name an alternative, but the sibling set makes the choice obvious.

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