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

Annotations already establish readOnlyHint=true and openWorldHint=true, so the description's job is to add context, and it does: it discloses the 25-articles-per-page chunking and that a page past the end is a valid empty page rather than an error. It also enumerates the returned metadata and article fields, which helps the agent know what it will receive. It omits whether the pageid has a default and what happens for out-of-range values beyond 'past the end', 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?

It is front-loaded with the core action, then the pagination caveat, then the discovery pointer — a sensible order with no filler sentences. The middle sentence is a dense field list that reads like a schema dump, which slightly blunts scannability.

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 two-parameter, paged read tool with annotations and an output schema, the description covers scope, paging behavior, and the id source, which is everything needed to call it correctly. Return values are described despite the output schema already covering them, so the extra detail is redundant but harmless.

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 baseline is 3; the description adds real meaning by explaining the page size behind pageid and the semantics of an empty page, which the schema only hints at. The id parameter's provenance is reinforced by the pointer to boardgamegeek_threads.

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?

Names a specific verb and resource ("Get a BoardGameGeek thread and one page of its articles") and scopes it to a single page rather than the whole thread. It also explicitly points at the sibling used for discovery, so the agent can distinguish it from boardgamegeek_threads without opening either schema. The doubled "Get Get" is a cosmetic typo, not a clarity problem.

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?

"Use boardgamegeek_threads to discover thread ids" gives clear routing guidance to the sibling that produces the required id, which matches the schema's requirement. It does not state exclusions (e.g., when to prefer a search or listing tool over fetching a known thread), so it stops short of full when/when-not coverage.

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