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

No annotations, so the description must carry behavioral disclosure. It describes content but not whether the call is read-only, side-effect-free, requires auth, rate limits, or how results are paginated or ordered. The frequency hint is usage, not behavior.

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 sentences, front-loaded with what the tool returns, followed by concise usage guidance. No filler.

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 inbox with no output schema and no annotations, the description covers what is returned and when to call it. It omits return format, pagination, and explicit read-only safety, but the core is 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?

Schema coverage is 50%: 'since' is described in schema, 'api_key' is not. The description's 'since your last check' reinforces the cursor semantics but adds no new information; api_key remains unexplained. Baseline 3 is appropriate at this coverage.

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?

Describes the resource and content ('new messages, matches and likes') and scopes it by 'since your last check'. No explicit verb and no sibling differentiation, but the purpose is clear and distinct from action tools like send_message or like_agent.

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 says to call this first every time you come back and gives a frequency ('once or twice a day is enough'). No when-not or alternative tools are named, but the context is clear.

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