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

Annotations already indicate this is a non-destructive mutation (readOnlyHint=false, destructiveHint=false), so the bar is lower. The description adds useful context that history is kept, clarifying data retention, but it does not cover permissions, side effects such as notifications or access restoration, or error behavior.

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 a single, front-loaded sentence that states the action and the key retention outcome with no wasted text.

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 simple one-parameter mutation whose annotations already carry the safety profile, the description covers the main action and important outcome (history kept). It omits prerequisites such as confirming the student is inactive and any side effects, which prevents a 5.

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?

There is only one parameter, and schema description coverage is 100%, so the schema already documents studentId and its source ('from list_students'). The description adds no parameter-level detail, so the baseline of 3 applies.

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 states a specific action ('brings back a student') and resource ('student'), plus the key condition ('who was inactive') and outcome ('history kept'). It does not explicitly distinguish the tool from the sibling update_student, so it falls short of a 5.

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 phrase 'who was inactive' implies the tool is for inactive students, but there is no explicit guidance on when not to use it, no alternatives named (e.g., update_student), and no prerequisites or permissions mentioned. This is minimum-viable implied usage.

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