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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is fully covered. The description adds only the return field names, which are also present in the output schema, and does not disclose calculation assumptions, formula, or limits beyond what annotations provide. No contradiction.

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 sentences, front-loaded with the purpose. The return values and cross-reference are brief and no filler is present. Every clause serves a purpose.

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 single-parameter, deterministic calculator with an output schema and safety annotations, the description is sufficient. It names the input concept and return fields; the output schema supplies exact structure, so no further behavioral detail is required.

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% and the sole parameter 'magnitude' is documented as 'Richter/moment magnitude' with a 0–10 range in the schema. The description says 'from its magnitude' but adds no format, unit, or range details beyond the schema. Baseline 3 applies when the schema does the heavy lifting.

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 ('calculate') and resource ('energy released by an earthquake') with the input basis ('from its magnitude'). The term 'earthquake' differentiates it from generic energy siblings such as calculate_kinetic_energy or calculate_energy_physics, so an agent can identify its scope 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?

No explicit when-to-use or when-not-to-use guidance is given. The phrase 'See list_bundles for related calculators' points to a catalog tool rather than stating when this calculator is appropriate versus alternatives. Usage is only implied by the purpose sentence.

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