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

Annotations already signal non-read-only and open-world behavior. The description adds valuable behavioral detail: a six-digit code is emailed, two sequential payloads are required, and no prior account is needed. It does not contradict the annotations.

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?

Three sentences deliver purpose, step-by-step protocol, and an example call with no filler. The most important information is front-loaded, and every sentence earns its place.

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 tool with no output schema, the description explains the expected result ('receive an API key') and the full invocation flow. It could be more explicit about the response field names, but the examples and protocol are sufficient for correct invocation.

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 schema only describes a generic 'input' object, but the description provides concrete payload examples for both phases: {'email':'...'} and {'signup_id':'...','code':'123456'}. This adds meaning far beyond the schema's minimal coverage.

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-resource pair: 'Start or complete Whisper signup from an email address alone, and receive an API key.' It also clarifies the two-phase nature of the operation and its outcome, making it unmistakable among the whisper_* siblings.

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 clear context for when to use the tool: when an API key is needed to unlock provisioning and governance skills, with no human step or prior account. It does not explicitly name alternatives or exclusions, but the signup purpose is distinct enough that this is a minor gap.

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