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

Annotations already declare a safe read operation, so the bar is lower. The description still adds real behavior: partial inputs fall back to page defaults, and the exact outputs (panel size, fixed costs, revenue at break-even, profit at 300/500 members) are disclosed up front.

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?

Front-loads the core question, then defaults, then return values, then a disclaimer — a sensible order with little waste. Four sentences for a 10-param calculator is reasonable, though the return-value sentence overlaps the output schema.

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 no required params, zero annotation gaps, and an output schema present, the description supplies everything else an agent needs: that omitted inputs default, and what the tool computes. Nothing essential for correct invocation is missing.

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 0% across 10 properties, so the description carries the burden and only partly meets it. It names the membership fee, salary goal, per-member cost and 'monthly overhead' conceptually, but never itemizes the seven distinct overhead fields (rent, staff, software, supplies, insurance, marketing, other) the agent must fill.

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 computation (break-even member count for a DPC practice) plus the exact inputs that drive it. The framed question distinguishes it from the sibling dpc_startup_cost, so an agent can route 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?

The only real guidance is 'Any input left out uses the calculator page's default,' which tells the agent partial invocations are allowed. There is no when-to-use/when-not framing and no explicit contrast with siblings like dpc_startup_cost.

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