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 value the annotations don't, by summarizing the returned payload (lines with products, quantities, prices) and giving the underlying endpoint, which matters because there is no output schema.

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, front-loaded with the return shape before the identifiers and the endpoint. The endpoint restatement is mildly redundant but useful for orientation; otherwise there is no waste.

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 two-parameter read with no output schema, the description supplies what an agent needs: the identifiers required and a sketch of the returned contract and its lines. A brief note on error behavior for an unknown subscription id would make it fully complete.

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 100%, with both ids fully documented including accepted gid:// formats, so the schema carries the semantics. The description only repeats that both ids are required, adding no format or constraint detail beyond the schema. Baseline 3 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?

The description names a specific resource, one subscription contract, and adds what it contains (lines with products, quantities, prices), which clearly separates it from the list_* siblings. What's missing is an explicit contrast with awtomic_list_customer_subscriptions or awtomic_get_origin_order, but the singular scope is obvious.

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 states the prerequisite (customer id plus subscription id), which implies this is a direct-lookup call, but it never says when to use this instead of awtomic_list_subscriptions or awtomic_list_customer_subscriptions. The agent has to infer that those are for discovery and this is for fetching a known contract.

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