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

Annotations declare readOnlyHint=true, so safety profile is known. The description adds the API endpoint and filter dimensions, but no pagination behavior (limit/offset interplay), no default page size, no return format details. For a list tool where pagination is critical, this is a significant behavioral gap.

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, zero waste, and the scope is front-loaded ('List subscriptions') before the filtering and endpoint details. 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 read-only list tool with full schema coverage and an annotation for safety, the description covers the basics. However, it omits pagination semantics (important given limit/offset params) and doesn't mention the output structure (no output schema exists, so the description could explain the return shape). Adequate but with clear gaps.

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%, so all parameter semantics (limit, offset, status, customer_id) are fully documented in the schema itself. The description adds only the fact that filtering is possible, which is redundant with the schema. Baseline 3 is appropriate when schema does the heavy lifting.

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 clear verb (List) and resource (subscriptions), and the description makes the scope explicit by noting the filter dimensions (customer or status). It's distinguishable from chargebee_get_subscription (single) but doesn't explicitly name a sibling alternative, so not 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?

The description implies the tool is for browsing/filtering subscriptions ('Filter by customer or status'), but it doesn't state when to use this vs alternatives like chargebee_get_subscription for a single subscription. No explicit when-not or exclusions are provided, leaving usage context to inference.

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