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 by structured data. The description adds no behavioral context beyond that (no caveats about assumptions, rounding, or the 'full version' limitation). With annotations carrying the load, 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?

Two sentences, front-loaded with the core comparison and no padding. The second sentence is a promotional pointer to the full version rather than functional information, which slightly dilutes the payload.

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?

An output schema exists, so return values need not be explained, and the 15 parameters are fully documented in the schema. However, for a 15-parameter financial tool the description is thin: it omits any note about the assumptions (monthly basis, currency behavior already in schema) or the limits of this 'short' version, leaving some context for the agent to infer.

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%, so the baseline is 3. The description loosely mirrors a few parameters ('platform fee plus overage') but adds no meaning, units, or constraints beyond what the schema already documents. No value is added over the structured fields.

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 uses a specific verb ('Compare') plus the three pricing models it contrasts (per-seat, usage-based, hybrid) and the input domain (small/mid/large customer mix). An agent can tell what it computes without opening the schema. It does not explicitly differentiate from any sibling, but there is no near-twin in the list, so the gap is minor.

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?

There is no statement of when to use this tool versus alternatives, no exclusions, and no prerequisites. Usage is only implied by the topic. Related siblings like seat_utilization_risk_assessor or pricing_elasticity_sandbox are never referenced as alternatives.

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