Convert a grade

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety behavior is covered. The description adds only that it maps across a named scale, with no mention of scale-dependent edge cases (e.g. an out-of-range percentage) — acceptable but not rich given annotations do the heavy lifting.

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?

Three short sentences, front-loaded with the purpose before inputs and example. Nothing is wasted, though the example prompt is somewhat illustrative filler rather than essential information.

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 present and read-only annotations, the description need not explain return values or safety. Inputs and scale selection guidance are covered; only cross-tool routing advice is missing, which is a minor gap for a low-complexity two-parameter 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% and both parameters are documented in the schema, including the enum list and default for scale. The description's example inputs ('B+', 87, '87%') duplicate what the schema already says, so it adds little beyond baseline.

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 (convert) and resource (grade) and states exactly what is returned: the matching letter, percentage range, and grade points. It is clearly distinguishable from siblings like calculate_gpa or needed_on_final, though it never explicitly names or contrasts them.

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 well-contextualized with a concrete example prompt and an explicit instruction to ask the student which scale their school uses when unsure. It stops short of stating when-not to use this versus calculate_gpa or weighted_grade, so it is clear but not fully routing-aware.

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