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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=true, so the mutation profile is largely covered. The description adds that either the name or the description can be targeted (a partial update), but says nothing about permissions, whether both fields can be sent at once, or consequences of a rename.

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?

A single short sentence that front-loads the action and the affected fields with zero filler.

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 four-parameter mutation with no output schema, the definition is minimally sufficient. It does not clarify that both mutable fields are optional, that at least one should be supplied, or what the call returns, leaving real ambiguity for the agent.

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 75% (fileId, studentId, and the 500-char description limit are documented). The description only loosely maps to the undocumented file_name parameter, so it adds no semantics beyond the schema. Baseline 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?

States a specific verb (changes) plus the exact mutable fields (name, description) and the resource (a file from list_student_files). An agent can distinguish it from unrelated update_* siblings, though it doesn't contrast with the closest analogues like update_media_caption.

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?

Referencing list_student_files implicitly establishes the discover-then-update flow, which is useful. However there is no explicit when-to-use/when-not guidance, no statement about prerequisites such as file ownership, and no named alternative.

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