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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful context beyond that: the operation is scoped to "Demo shop (sample data)" and only one status can be applied at a time. It omits return format and any pagination or limit behavior.

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 short sentences with the resource and scope front-loaded; there is no filler. The bracketed "[Orders]" tag and demo-shop note are compact enough to justify their space.

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-param, zero-required tool with an output schema and full annotations, the description is adequate: it covers what is counted and the filter. The environment scoping (Demo shop) is a helpful clue, but the absence of any sibling routing or filtering caveats leaves it merely sufficient.

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 50%: the status enum is self-documenting and the account param carries its own description. The description's "optionally in one status" clarifies that the filter is a single value only, but adds no syntax or meaning beyond that, so 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?

States a specific verb (count) and resource (orders) with an optional status filter, so it is distinguishable from orders_list. It does not, however, explicitly name a sibling or state how counting differs from listing, keeping it short of a 5.

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?

"optionally in one status" implies a filtered count use case, but the description never says when to choose this over orders_list or orders_get. Usage must be inferred from the tool name and the single-status hint.

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