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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and reach profile is covered. The description adds only the underlying REST endpoint (GET /api/v1/get_subscription); it says nothing about not-found behavior, response shape, or auth requirements, so this is baseline rather than additive.

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 no filler, and the purpose is front-loaded ahead of the endpoint detail. Every sentence earns its place.

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 single-parameter read tool with no output schema, the definition is sufficient: identity, lookup key, and read-only nature are all clear. The only shortfall is the absence of any hint about the returned object or the not-found case.

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% and the single parameter is fully documented by the schema ('Subscription id.', integer > 0). The description adds no format, sourcing, or constraint detail beyond 'by id', so the schema carries the weight and a 3 baseline applies.

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 ('Get one subscription by id') and glosses the domain term as 'membership package', so the agent knows what is being fetched. It implicitly distinguishes itself from the sibling gingr_list_subscriptions by being the singular, id-keyed lookup, but never names that sibling explicitly.

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?

The phrase 'by id' implies usage (call it when you already hold a subscription_id), but there is no explicit when-to-use versus when-to-use-an-alternative guidance. The agent must infer that gingr_list_subscriptions is the route when no id is known.

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