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

Annotations already declare readOnly, idempotent, closed-world and non-destructive behavior, so the safety profile is covered. The description adds genuinely useful context beyond that: the specific record categories retrieved and the 2-4 ID arity constraint. It stops short of describing how results are presented (per-ring blocks vs. side-by-side comparison), which would be the remaining gap.

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 short sentences, zero filler, with the data scope front-loaded and the exclusion tacked on at the end. Nothing to trim.

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 annotations covering safety and no output schema, the description carries the return-value burden and does list the record categories returned. It is nearly complete; only the shape of the comparison result is left unspecified.

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% and the single parameter is named only 'ids' with bare string items, so the description must compensate. It does clarify that the strings are ring IDs and confirms the two-to-four range, but that range merely restates the schema's minItems/maxItems rather than adding new meaning.

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 (Read) and resource (evidence, limitations, sizing, battery and subscription records) scoped to two to four ring IDs. An agent knows exactly what data comes back, though the description never names or contrasts the sibling tools (search_rings, calculate_ring_cost) it could be confused with.

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 negative clause 'Not a hands-on review or diagnosis' implies a usage boundary, but no positive when-to-use context and no explicit alternative is offered. An agent must infer that search_rings finds IDs and calculate_ring_cost handles pricing.

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