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

Annotations already cover the safe-read profile (readOnly, idempotent, non-destructive, closed-world). The description adds value beyond them by disclosing the returned columns, the per-row 'access mode' signal, and the prerequisite 'Requires connecting a Valet account'. Pagination or result-size behavior is left unstated.

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?

Purpose leads, guidance follows, constraints close — a sensible front-loaded order. There is mild redundancy in 'Each row says its access mode', which repeats the access-mode field already listed in the opening sentence.

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 list tool with no output schema, the description covers what is returned, how to narrow, and the auth prerequisite. It omits any pagination/limit or ordering caveat, which is the only material gap.

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 100%, so both parameters are already documented, including the org_name default. The description's 'Pass kind to narrow to one kind' only restates the schema enum, and org_name is never mentioned, so it adds no meaning beyond the structured fields.

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 gives a specific verb-resource pair (List) over a precisely defined resource set ('every website, app, and agent') and enumerates the fields each row carries (kind, URL, access mode, last published). Combined with the title and the reading guidance, an agent can distinguish this from sibling reads like get_service without opening the schema.

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 states a concrete when-to-use rule: 'the first read when the user names something and you do not know what it is', plus the recovery use case for names scrolled out of context. It does not name the alternative (get_service) or state when not to use it, so it falls short of the explicit routing seen in the top example.

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