Get my grades (all courses)

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

Annotations already indicate readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows this is a safe read operation. The description adds minimal behavioral context beyond saying 'current grade' and 'every active course', which clarifies scope but does not describe return format, pagination, or other operational details. Since annotations cover the safety profile, a 3 is appropriate.

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, concise sentence that immediately states the purpose without any fluff or redundant phrasing. It is front-loaded and every word adds value, making it highly efficient.

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 zero-parameter read-only tool with clear annotations, the description is sufficient to understand what the tool returns (current grades for all active courses). It does not elaborate on edge cases like what counts as 'active' or the format of the grade, but given the tool's simplicity and the annotations, this is acceptable. The description could potentially mention that it aggregates across courses, but it already implies that.

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?

The tool has zero parameters and the schema is empty, so there is nothing for the description to clarify. With no parameters to document, the description is not required to add parameter-level semantics, and the baseline score for such cases is 4.

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 'Your current grade in every active course' uses a clear verb and resource, and explicitly states the scope (all active courses), which helps distinguish it from the more specific canvas_get_course_grade tool. It is not a tautology and conveys a specific action and result, though it does not name sibling tools directly.

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 no guidance on when to use this tool versus the many sibling tools, such as canvas_get_course_grade for a single course or canvas_get_missing_submissions for outstanding work. It simply states what it does, leaving the agent to infer usage context from the tool name and title.

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