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

With no annotations at all, the description carries the full behavioral burden; it does disclose the meaningful ordering behavior ('soonest renewal first'), which the schema does not. However it says nothing about pagination, result limits, cache freshness, or whether cancelled plans are returned by default — real gaps for a pure read tool with zero annotation coverage.

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 well-formed sentence with no filler; the scope, the two optional filters, and the sort order all come before any padding.

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?

No output schema and no annotations means the description is the only behavioral source, and it covers filtering plus ordering but not the return shape, result size, or pagination. Adequate to invoke the tool, not complete enough to predict what comes back.

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 0%, so the description must compensate, and it does: 'a shop's' maps to shop_id, 'for one customer' to customer_id, and 'by status' to the status filter. It stops short of explaining the active/cancelled enum semantics or confirming shop_id is required, which keeps it from a 5.

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 identifies the resource (a shop's maintenance plans) and the two optional narrowing dimensions plus ordering, which is enough to separate it from maintenance_getPlan / createPlan / cancelPlan. The only weakness is that the verb is implicit in the noun phrase rather than stated outright.

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?

It says the customer and status filters are optional, which implies the browse-style use case, but it never states when to prefer this over maintenance_getPlan for a single plan, nor does it name any alternative. Usage is inferable rather than guided.

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