arcsin

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

No annotations are provided, so the description carries the full burden. It discloses the output unit (radians), which is genuinely useful for a math op, but it omits the critical domain constraint that the input must lie in [-1, 1] and what happens outside that range. For a pure, stateless function this is adequate but not rich.

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 short sentences, zero filler, with the primary purpose front-loaded and the batching hint second. Nothing is wasted.

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 one-parameter stateless math function with no output schema and full schema coverage, the description covers purpose, unit, and the batching escape hatch. The only real gap is the missing input-domain constraint, which an agent genuinely needs to avoid a NaN or error.

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 100% for the single 'number' parameter, so the schema already documents it fully; baseline is 3. The description adds only the radians unit of the result, which is not parameter syntax and doesn't meaningfully extend the schema.

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 operation (arcsine) on a specific input (a number) and pins the unit (radians), which distinguishes it from degreesToRadians and radiansToDegrees siblings. An agent can select it without opening the schema.

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?

Explicitly routes multi-step work to batch_calc, which is a clear alternative-selection rule. It does not, however, say anything about when this single-operation form is preferred or note the sibling sin/arccos relationship, so the routing is partial rather than complete.

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