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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false. The description adds minimal behavioral context beyond the purpose (e.g., it does not mention rate limits, auth requirements beyond the API key parameter, or that results may be incomplete). It does not contradict 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?

The description is concise: two sentences that immediately state the action and outputs, followed by an example. Every part adds value, and there is no unnecessary text.

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?

Given the tool's simplicity (2 parameters, no output schema, no nested objects), the description covers what is needed. It states input, output, and provides an example. No missing context given 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?

Schema coverage is 100%, so the schema already describes both parameters. The description adds an example call with realistic values, which helps clarify how to use the parameters. This addition slightly improves understanding beyond the schema's descriptions.

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 clearly states the tool's purpose: 'Look up the person/LinkedIn profile behind an email address'. It specifies the input (email) and outputs (name, company, job title, LinkedIn URL). The verb 'Look up' and resource 'person/LinkedIn profile' are specific. The tool name includes 'reverse_email', which contrasts with the sibling 'findymail_find_email', providing implicit distinction.

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 description includes an example call and explains what the tool does. However, it does not explicitly state when to use this tool over its sibling 'findymail_find_email' or other tools. The naming implies the direction, but explicit guidance would be clearer.

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