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

Annotations already establish that this is a safe, read-only operation. The description adds useful context by listing the returned plan fields and recommending the pre-send check. It does not cover auth, rate limits, or error behavior, but those gaps are minor for a zero-parameter read endpoint.

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 two sentences plus the endpoint path, with the returned fields and the usage recommendation front-loaded. Every sentence adds value and there is no unnecessary repetition.

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 zero-parameter, read-only tool with no output schema, the description provides enough detail: it enumerates the returned plan attributes and gives a practical reason to call it. No additional information is needed to invoke it correctly.

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 tool takes no parameters, so there are no parameter semantics to explain. The empty schema is consistent with the description, and the baseline for zero-parameter tools is a 4.

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 identifies the resource as the account's current Emailchef plan and enumerates what it returns: plan name, expiry, contact/send limits, credits, and active/expired flags. It does not explicitly distinguish this from sibling tools like emailchef_get_account or emailchef_get_sms_balance, which slightly limits clarity.

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 a concrete usage cue: 'Check this before a big send.' This tells the agent when the tool is relevant. It does not name alternatives or exclusions, but the context is clear enough for a straightforward read tool.

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