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

Beyond the readOnlyHint annotations, it discloses that full keys are never returned (security posture), the exact authorization requirement ('account:read'), the permission nuances for product-line-limited vs unrestricted keys, and that the call is free. That is substantive behavioral context an agent cannot get from the annotations or schema.

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 returned-field list is front-loaded and every clause carries information (fields, security caveat, auth requirement, cost). It is dense and the permission discussion runs long as one sentence, but none of it is filler for a tool whose entire value is in knowing what comes back and what authorization it needs.

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?

There is no output schema, yet the description compensates by enumerating the returned fields, so an agent knows the shape of the response. Combined with permission requirements and the free-cost note, nothing needed to call this zero-param listing tool correctly 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?

The tool takes zero parameters, so the baseline is 4 and there is nothing for the description to disambiguate. It correctly implies a full-account, unfiltered listing rather than suggesting any hidden filtering options.

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 opens with a specific verb and resource ('Every API key of the account') and enumerates exactly which fields are returned (name, prefix, status, permissions, rate limit, IP restriction, expiry, last use). This clearly separates it from the mutating siblings everyinfra_key_create, everyinfra_key_delete, everyinfra_key_disable and everyinfra_key_update.

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 explicit when-not guidance: 'Never returns a full key; create, limit or disable keys in the console,' which redirects the agent away from this tool for mutations. The only weakness is that it points to the console rather than naming the sibling key-management tools that exist in this toolset, which could misdirect an agent that has everyinfra_key_create/delete/disable available.

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