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

Goes well beyond the annotations by disclosing the one-time-use semantics, the 10-minute expiry, the recovery path ('a new one can be requested if it lapses'), and the handling constraint that the agent must not open or share the URL. The annotations only declare the safety profile (readOnlyHint=false, idempotentHint=true, destructiveHint=false); the description supplies the operational behavior an agent actually needs.

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 compact sentences, front-loaded with what the tool creates, followed by consumption rules and lifecycle constraints. Every clause earns its place; nothing is redundant with the title or schema.

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?

An output schema exists, so return values need no explanation, and the description covers the full lifecycle of the artifact it produces: creation, one-time use, expiry, and re-request. Nothing an agent needs to call and handle this tool correctly 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?

There is a single parameter with 100% schema description coverage, so the schema already fully documents idempotency_key. The description adds no parameter-level meaning, which is the expected baseline of 3 when structured data carries the load.

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 and resource ('Create a one-time link') and names the exact outcome: signing the agent's person into their netsi web settings without a password or Google. No sibling tool overlaps with this function, and an agent can immediately tell what it produces.

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 specifies who consumes the result ('The url is for the person to open in a browser') and explicitly excludes the agent ('It is never opened by the agent nor shared with anyone but the person'), which is strong routing guidance. It stops short of stating prerequisites or when to prefer this over any alternative flow, so it lands at 4 rather than 5.

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