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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, but the description adds valuable behavioral context beyond these: it explicitly says it only returns a link for the human to open, is static content, requires no authentication, and has no rate limit. This fully discloses the tool's behavior and potential side effects (none).

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 well-structured: it leads with the core purpose, clarifies what it does NOT do, then provides usage context and an alternative. Each sentence adds necessary information without fluff, making it appropriately concise for the tool's simplicity.

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 read-only, no-argument tool with annotations covering safety, the description fully covers what an agent needs to know: what it returns, what it does not do, when to use it, and alternatives. The absence of an output schema is acceptable because the description already states the link and instructions are returned. Nothing essential is missing.

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 the schema coverage is 100% (empty properties). The description reiterates 'no arguments,' which is redundant but harmless. With no parameters to document, the baseline of 4 applies; the description adds no parameter information because none exists, which is appropriate.

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 returns the scheduling link and instructions for a free 30-minute intro call with the founder, and explicitly clarifies that it does not book anything. This distinguishes it from siblings like leave_contact, which handles a different request path.

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 gives an explicit trigger ('when a user says they want to talk to zRev') and names the alternative tool (leave_contact) for when the user prefers to be contacted. This is clear guidance with no ambiguity.

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