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

Annotations already declare readOnlyHint=true, so safety is covered, and the description adds genuinely new behavior: zero-based paging and the "follow next_page until null" termination rule, which governs how to drain results. It does not disclose rate limits or the shape of a client record, but for a read-only list tool this is solid.

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 short sentences, all load-bearing; purpose is front-loaded before the pagination mechanics and the alternative-tool pointer. Nothing redundant or padded.

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 2-parameter, no-required-args read tool with readOnlyHint and no output schema, the description covers purpose, paging loop, and the filtered alternative — enough to invoke correctly. The only gap is that it never hints at what a client record contains or whether default limit of 100 is applied automatically.

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 'page' (zero-based) and 'limit' (max 1000) are already documented. The description adds value beyond that by explaining the iteration contract — start at page 0 and continue while next_page is non-null — which is not expressible in the schema.

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?

Specific verb + resource + scope: "List one page of Hub Planner clients" tells an agent exactly what this returns and that it is paginated, distinguishing it from hubplanner_get_client. Sibling differentiation is only partial because the redirect points at "the search tool where available" rather than a named sibling (and no hubplanner_search_clients exists).

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?

Clear usage context: use this for the unfiltered paginated listing and follow next_page until null. The alternative path is stated but hedged ("the search tool where available"), which leaves the agent to figure out which tool that is; no mention of when to prefer get_client for a single record.

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