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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds that the tool returns an 'arithmetic scenario range' and that evidence may be null, plus a privacy boundary. It omits what the comparison produces (surplus/shortfall direction) and how low/base/high are combined, leaving meaningful behavioral gaps.

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?

The core constraint is front-loaded in the first sentence, but the remainder is a string of procedural asides ('Put tool fields inside inputs', 'Do not pass the REST calculator field inside MCP arguments') that mostly address protocol plumbing rather than helping the agent call the tool. Several sentences could be merged or dropped without losing meaning.

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 annotations cover safety. Still, a tool with a deeply nested two-parameter schema at 0% description coverage needs more: the demand/capacity sub-field semantics and the meaning of the returned range are absent, making it incomplete for the tool's complexity.

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?

With 0% schema description coverage, the description must carry the load, and it partially does: it clarifies that all fields go inside 'inputs', that demand/capacity may be null when evidence is unavailable, and that geography, period, and units must be matched. It adds nothing about low/base/high ranges, basis enum choices, source, or asOf, so the nested object semantics remain largely undocumented.

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 states a specific action ('Compare public or non-sensitive figures') with matching constraints on geography, period, and units, which conveys the general idea. However, what is actually being compared (demand against available capacity, as the title implies) is never spelled out in the description, and no sibling tool is referenced for differentiation. An agent must infer the core computation from the title.

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?

It gives partial usage rules: use null for unavailable evidence, exclude private/personal records, and supply units or modelVersion only when present in inputSchema. These are data-handling constraints rather than selection guidance. Nothing tells the agent when this tool is preferable to related calculator tools or what prerequisites (e.g., matched periods) must hold.

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