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

The readOnly annotation already establishes the safety profile. The description adds the GET endpoint and the filtering scope, but does not disclose pagination behavior, result shape, or any limits/edge cases. It adds some context but does not go beyond what one would expect from a simple read-only list operation.

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 core action and filter capability. The endpoint detail is minor but not harmful; nothing is verbose or redundant enough to reduce the score significantly.

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 low-complexity read-only list with no required parameters and fully documented schema fields, the description is sufficient to invoke the tool. It lacks explicit alternative guidance and return-type detail, but those are not critical here given the annotations and schema richness.

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?

Input schema description coverage is 100%, so the schema already fully documents limit, offset, status, and customer_id. The description only paraphrases the customer_id and status filters and adds no missing parameter semantics or examples.

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 uses a specific verb and resource ('List subscriptions') and identifies the main filtering dimensions (customer, status). It clearly indicates a bulk read operation, but it does not explicitly differentiate itself from the related get_subscription or other list_* siblings.

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 description implies usage: use it when you want to list subscriptions and optionally filter by customer or status. However, it does not state when to prefer get_subscription for a single subscription or when not to use this tool, leaving the choice partly implicit.

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