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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the behavior that the calculation reports both the delayed revenue and a halved-delay recovery scenario, which is useful, but it says nothing about units, currency handling, or what the result contains.

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?

One tightly written sentence front-loads the core computation. The trailing promotional URL is the only wasted token, but it does not obscure the 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 simple three-parameter read-only calculator with full schema coverage and no output schema, the description conveys what is computed and the dual output (delay cost plus halving benefit). It is complete enough to invoke correctly, with only minor gaps around output units.

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 acv, delayWeeks, and dealsPerYear are each documented in the schema itself. The description adds no unit, range, or format detail beyond that, so the baseline of 3 applies.

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 names a specific verb ('Estimate') and a precisely scoped resource: revenue delayed by the onboarding gap between signature and go-live, plus the recovery from halving it. This distinguishes it from near-neighbors like lead_routing_delay_cost_calculator and contract_redline_duration_predictor without needing to open any 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?

There is no statement about when to reach for this tool versus the many other cost/delay calculators in the sibling list, nor any prerequisites or exclusions. The only extra guidance is an outbound link, which does not tell the agent when this model applies.

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