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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds the output shape and the token-scoping constraint, which is useful, but nothing about pagination or result ordering. With rich annotations, this is adequate but not additive enough for a higher score.

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?

Two short sentences with zero waste. The core purpose and the output shape are front-loaded, and the pointer to the alternative tool follows immediately.

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?

With an output schema present and annotations covering the safety and mutability profile, the description needs only to explain purpose and routing, which it does. A minor gap is that it doesn't clarify whether the resource enum narrows results or how many endpoints are returned, but nothing critical is missing.

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% and the sole 'resource' parameter has an enumerated description, so the schema already carries the semantics. The description adds no filter syntax or behavior beyond what the schema states, which is the expected baseline when the 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 specific verb and resource ('List the REST API endpoints') and scopes it to what an API token can use, plus the returned shape (method, path, title). It also names the sibling get_api_endpoint, so an agent can distinguish this list tool from the detail tool immediately.

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?

Explicitly routes the agent: 'Get one in full with get_api_endpoint.' The condition (want full detail on a single endpoint) is clear. It doesn't spell out when-not to use this list tool or mention filtering behavior for the resource enum, so it stops short of a 5.

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