Retrieve a subscription

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is fully covered; the description contributes nothing beyond that. It does not mention error behavior for unknown ids, nor any auth or rate-limit context that would add value.

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?

It is a single short sentence with no filler, but that brevity comes from under-specification rather than tight editing; nothing is front-loaded because there is nothing to load.

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 lookup-by-id tool with no output schema, the description should say what is returned or what happens on a missing id. Annotations cover the safety profile and the schema covers the parameter, but the agent still learns nothing about the response or failure modes.

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?

Only one parameter exists and schema description coverage is 100% ('The object's id.'), so the schema carries the burden and the baseline is 3. The description adds no syntax hint (e.g. a 'sub_...' prefix) or detail about what the id identifies.

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 'Retrieve a subscription' merely restates the tool name and title verbatim, adding no scope, no resource qualifiers, and no differentiation from siblings like list_subscriptions or retrieve_invoice.

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?

There is no guidance on when to use this tool versus list_subscriptions for browsing, nor any stated prerequisites such as required permissions or the id format. The agent must infer everything from the name.

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