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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile needs no restatement. The description adds genuinely useful behavior beyond that: the tool is dual-mode, and calling it on a Pad returns the shared text itself. It does not describe result structure, pagination, or ordering of the file/folder list.

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 compact sentences with no filler, front-loading the primary listing behavior before the fileId variant. The parenthetical definition of a Pad is a small but justified clarification.

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 read-only two-parameter tool with full schema coverage and annotations, most of what an agent needs is present. With no output schema, however, the description says nothing about the shape of the returned file/folder listing (fields, ordering, whether folders nest), leaving a notable gap for a listing tool.

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 100%, including descriptions that fileId comes from a first call and courseId from list_courses, so the baseline is 3. The description adds the important semantic that fileId switches the tool from listing to detail retrieval and that Pad files yield their text, which is meaningfully more than the schema's 'read that File'.

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 gives a specific verb-resource pair ('Lists a Course's Files and Folders') and explicitly describes a second mode when fileId is supplied, including the Pad text special case. It is clear what the tool does, though it does not distinguish itself from siblings such as get_course_page or list_members.

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?

Usage is implied rather than stated: the two-mode structure (list without fileId, read details with fileId) suggests when to use which form, and the schema reinforces fetching fileId from a first call. However, no alternatives or exclusions are named, so an agent must infer that this is the right tool for course file content versus other course resources.

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