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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds behavior beyond that: result ordering (newest first), page size ceiling, and the important constraint that the page token must be passed 'with the same other arguments' for the next page, which is a real pagination-consistency rule not visible in 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?

Two dense sentences plus the endpoint literal; the entity definition, ordering, paging, and filter examples are all front-loaded with no filler. Every clause carries operative information.

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 read-only list tool with no output schema and full schema description coverage, the description covers paging, ordering, and filtering adequately; mentioning nextPageToken implies the reply shape. Minor gap: it never says what a returned plan object contains, though that is partly excused by the entity definition and absent output schema.

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; the description goes slightly beyond by showing how the free-form filter object is actually shaped in practice and by restating the same-arguments requirement for page_token. It does not, however, explain the semantics of the free-form nested filter fields beyond the two examples.

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 and resource ('List route plans'), then defines the domain entity ('a plan = one day's delivery job: date, depot, drivers, routes') and the ordering/paging scope. An agent can distinguish this from sibling list tools like spoke_list_plan_stops or spoke_list_depots without opening any schema.

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?

Gives concrete usage context: newest-first ordering, pages of up to 20, and filter syntax examples ({"title":"Monday run"}, {"startsGte":"2026-10-01"}). It does not state when NOT to use this tool or point to alternatives such as spoke_get_plan for a single plan, so it stops short of full routing guidance.

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