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

The description adds meaningful behavior beyond the annotations: the URL is 'signed' and 'expiring', and it states the return shape `{ url, viewToken, expiresAt }`. However, it does not disclose whether issuing a URL creates server-side state, consumes a session, or revokes previous links, and with readOnlyHint=false and openWorldHint=true this information would be useful. It partially compensates for weak annotations but leaves implicit side effects.

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, each with a distinct job: action+behavior, use case, and return shape. The most important information is front-loaded and there is zero 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 tool with no output schema, the description provides the return shape, purpose, and usage scenario, which covers most of what an agent needs. The remaining gap is parameter-level detail (sessionToken, expiresSeconds), which was already penalized in parameter_semantics. Overall, the description is nearly complete for a simple URL-issuing tool.

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 description coverage is only 50% (hatchId and tenantId are documented). The description adds 'any tier' and 'expiring', loosely tying to hatchId and expiresSeconds, but it never explains sessionToken or how expiresSeconds should be set beyond the schema's min/max. Since the schema leaves two parameters undocumented and the description does not compensate, this is a clear gap.

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 opens with a precise verb+resource pair: 'Issue a signed, expiring guest view URL', and qualifies it with 'for any tier' and the concrete `?vt=…` format. This clearly states what the tool does and fully distinguishes it from any sibling tool, none of which overlap with sharing/guest access.

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 second sentence gives an explicit use case: 'Use for private run reports without the shared site password.' This tells an agent the exact scenario where this tool is appropriate. It doesn't name alternatives or exclusions, but the share function is unique among the sibling list, so the contextual guidance is strong enough.

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