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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds one behavioral detail beyond the schema: results are ordered by most recently updated. It does not disclose any result-count cap, pagination behavior, or what happens for an empty account, which are the traits an agent would still want here.

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?

Two sentences, zero filler, and the primary trigger is front-loaded ahead of the sibling redirect. Every clause earns its place by either stating scope or routing to an alternative.

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, the single parameter is fully documented in the schema, and annotations cover safety. The description supplies the usage routing that the structured fields cannot. The only gap is not stating how many sites are returned or whether the list is capped, which matters for a 'most recently updated' listing.

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?

Only one optional parameter and schema description coverage is 100% ('Only sites in this workspace, from get-account. Leave out for all of them.'), so the schema already carries the full semantics. The description adds nothing about workspace_id, so the baseline of 3 applies.

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 states a concrete verb and resource ('Lists their most recently updated sites') and adds scope via the 'most recently updated' ordering. It also implicitly distinguishes itself from siblings like get-site and show-preview by framing itself as the multi-site listing for a user. The opening sentence is usage-first rather than purpose-first, which slightly softens the statement of what the tool does, but the intent is unambiguous.

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 an explicit trigger ('when the user asks which WebTwizz sites they have, or wants to pick one to work on') and an explicit alternative with its own condition ('when the user names a site they want to see, use show-preview with its name instead'). An agent can route between the two tools without inference.

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