List email activations

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

With no annotations provided, the description carries the full burden and does an excellent job: it discloses the ordering behavior, the 100-row cap, the lack of cursor paging, the API key requirement, and the important side-effect fact that it does not spend. These go well beyond the schema and give the agent a clear behavioral model.

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, each carrying a distinct fact: the core purpose, the paging/limit behavior, and the auth/side-effect notes. The most important information is front-loaded and there is zero 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, single-optional-parameter list tool with no output schema, this description covers everything an agent needs to invoke it correctly: what it returns (a list of recent email activations), the ordering, the limit, the paging limitation, authentication, and cost side-effects. Nothing obvious 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% for the single limit parameter, so the schema already documents its range and default. The description's mention of 'up to 100' simply echoes the schema's maximum and adds no new meaning. Baseline 3 is appropriate because the schema handles the parameter semantics.

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 states a specific action and resource ('List your most recent email activations') and adds concrete scoping details (newest first, up to 100, no paging). The 'email' qualifier clearly distinguishes it from the sibling list_activations, so an agent can tell them apart without opening schemas.

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?

It gives clear context about when this tool is appropriate: for listing recent email activations, with limitations (no cursor paging, up to 100) and prerequisites (API key). It does not explicitly name alternatives or state when to use list_activations instead, so it stops short of a full when-not/exclusion guide.

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