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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds valuable information beyond that: the required OAuth scope (certs:manage), the exact API path (GET /manage-certs), and a warning not to invent other paths. It also notes shared API, billing, and rate limits, giving the agent operational context without waiting for errors.

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?

The description is compact (four sentences) and front-loads the core purpose. The opening 'List certificates' is slightly redundant with the tool name, but the subsequent details (scope, path, rate limits) are useful. It avoids unnecessary fluff and stays efficient.

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 simple read-only list operation with one optional parameter, the description covers the essential call context: scope, endpoint, and operational constraints. It does not describe the return format or pagination, but with no output schema and a straightforward 'list' semantics, the implications are clear. Given annotations already handle safety, this is adequately 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?

The single parameter x_app_id is fully described in the input schema (100% coverage), including when to use it ('set it only for multi-app orgs'). The description does not mention parameters at all, so it adds no extra meaning beyond the schema. Baseline 3 applies because schema coverage is high.

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 clearly states the tool lists certificates for the current app, with a specific verb and resource. It also provides the OpenAPI operationId and GET path, making the purpose unambiguous. However, it does not explicitly contrast with sibling list tools (e.g., listApiKeys), so it stops short of full differentiation.

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 use when needing all certificates for the current app ('Returns all certificates for the current app'), and adds a scope requirement ('Scope: certs:manage'). It does not explicitly state when not to use it or name alternatives, so usage guidance is implied rather than explicit.

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