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

Annotations already establish readOnlyHint and openWorldHint, so safety is covered. The description adds a real behavioral trait beyond that: results are ranked by page views, which tells the agent how to interpret ordering. It doesn't cover pagination or result-size behavior, keeping it from a 5.

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?

A single front-loaded sentence: resource and matching semantics come first, ordering second, examples last. No 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?

With no output schema, the description usefully discloses that results are ranked, and the schema supplies the time window and limit defaults. An agent has enough to call it correctly, though a note on empty results or the default 7-day window being only from the schema 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 coverage is 100%, so the baseline is 3, but the description's concrete examples ("/blog", "pricing") clarify what the query parameter accepts — substrings of the path rather than full URLs — which the schema alone states more abstractly.

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 names the resource (pages) and the matching rule (path contains a substring) plus the ordering (ranked by page views), which is more than a tautology. It doesn't explicitly differentiate from siblings like list_pages or search_events, so it stops short of a 5.

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 phrase "a slug you half remember" implies the use case — fuzzy/partial lookup when you don't know the exact path — but there's no explicit statement of when to prefer this over list_pages or how it differs from search_events. Usage is inferred, not stated.

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