get_esim_status

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

It explicitly discloses that this is a read operation and that it combines two API calls in parallel, which is useful behavioral context beyond a vague 'get status'. With no annotations, this partially covers safety and request structure, though it omits response format and error 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 concise sentences, with the first front-loading the main purpose and the second adding endpoint detail. No wasted words.

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?

Given the tool's simplicity—one required parameter and no output schema—the description covers the key returned categories and the combined-call behavior. It lacks detailed output/error information, but that is less critical here.

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 input schema has one required parameter, esim_id, with no description, and schema description coverage is 0%. The description does not explain the parameter or its format; it only weakly implies it via 'an eSIM's'.

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 uses the specific verb 'Read' and clearly identifies the resource: an eSIM's current status, plan info, and data usage. Mentioning that it combines two endpoints (GET /v1/esims/:id + /usage) distinguishes it from sibling tools like get_esim_qr.

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 clearly states this tool is for reading eSIM status and usage, providing appropriate context for when to use it. It does not explicitly name alternatives or state when not to use it, but the sibling list makes alternatives obvious.

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