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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds the important behavioral detail that results come from the site's latest run (data freshness), which the schema does not say. It also enumerates the returned fields, though it does not discuss pagination behavior beyond what offset/limit imply.

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 tightly packed sentences with the resource and scope front-loaded, then the narrowing option. Nothing is repeated and no filler appears.

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 nine-parameter read-only listing tool with no output schema, the description supplies the key facts an agent needs: source run, returned fields, and the failing filter. It stops short of explaining sort direction defaults or result paging semantics, which would round it out.

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 the schema already documents all nine parameters including enums for kind, sort, and dir. The description only echoes the 'failing rule' filter and the field set, adding no syntax or example values beyond the schema; baseline 3 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?

States a specific verb (list) and resource (a site's pages) with the scope 'from its latest run' and lists the returned fields (status, depth, words, failing rules). It implicitly contrasts with the singular mttr_page and with aggregate siblings, but never names an alternative, so differentiation is left to inference.

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 sentence 'Can be narrowed to the pages failing one rule' gives a usable condition for the failing filter, which is implied guidance. But there is no explicit when-to-use vs when-not, no mention of when to prefer mttr_page (single page), mttr_search, or mttr_rules, and no prerequisites such as needing a completed crawl.

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