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

With no annotations, the description carries the behavioral disclosure burden and does so well: it declares the operation is inspection-only, states it does not return analytics, and lists exactly what it shows. It does not cover error behavior or auth prerequisites, but the negative scope and output contents are clearly disclosed.

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 description is front-loaded with the most important scoping statement, then organized into clear USE WHEN bullets and an explicit alternative. Every sentence earns its place without redundancy or filler.

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 zero-parameter read-only tool, the description gives complete operational guidance: what it returns, when to use it, and which sibling to choose for data questions. The presence of an output schema means the description need not restate return structure in detail.

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?

The tool has zero parameters and an empty input schema, so there is no parameter semantics to add; the description correctly avoids inventing parameter details. This matches the baseline for a parameter-less tool.

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 precisely identifies the tool as API key inspection, enumerates the exact output fields (key name, prefix, container access count, expiry), and explicitly negates any analytics role, which distinguishes it from data-focused siblings like get_summary and get_report.

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 'USE WHEN' section gives concrete triggers, including the user asking about connected account/key or key expiration, and an authorization-error scenario. It also explicitly states when not to use it, directing data questions to get_summary or get_report.

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