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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds value by disclosing the underlying source ('Wikimedia Analytics REST API (wikimedia.org/api/rest_v1)') and that 'no auth required' – useful operational context beyond the annotations. It doesn't cover rate limits, but the bar is lower given the rich annotations.

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 earning its place: the first states the core action and options, the second gives the usage workflow with a sibling, and the third names the underlying API and auth requirement. Front-loaded and zero waste.

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?

The tool has an output schema, so return format is covered by structured data. The description covers scope, filters, granularity, usage context, the underlying API, and auth requirements. Nothing an agent needs to call this correctly appears to be missing.

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 all parameters (project, article, start, end, agent, access, granularity) are already documented with types, formats, and defaults in the schema. The description mentions access method, traffic agent, and granularity, but adds no meaning beyond what the schema already provides. 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?

The description states a specific verb ('Get'), a precise resource ('pageview history for one specific article on a Wikimedia project'), and the key constraints (date range, daily/monthly buckets). It also explicitly distinguishes itself from the sibling tool pageviews_top by framing itself as the follow-up for trend history, so an agent can tell them apart immediately.

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 description explicitly names a sibling ('wikimedia-analytics.pageviews_top') and provides a concrete workflow ('Use after ... to track trend history for a discovered article'). This gives a clear when-to-use context and an alternative, though it does not explicitly state when not to use the tool or mention other related siblings like aggregate.

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