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

Annotations already declare readOnly/openWorld/non-destructive, so the description spends its words well beyond that: it explicitly guarantees access keys and passwords are never returned (a security-relevant guarantee not in the schema) and discloses that the response includes hourly API quota consumption, which is operationally important.

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 compact sentences front-load the core identification, then add the two details an agent most needs (no secrets returned, quota usage included), closing with the endpoint path. Nothing is redundant with the title beyond the unavoidable identification of the resource.

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?

With no output schema, the description carries the burden of return-value explanation and does so at a reasonable level: company/contact details, account settings, and rate-limit usage. Minor gaps remain — response shape granularity and whether the quota figure is a count vs. a limit are unstated — but the essentials are covered.

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 there is nothing to disambiguate; the schema is empty and coverage is effectively complete. The description correctly spends no space on parameter explanation.

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?

States a specific verb and resource — retrieves the IDX Broker client account associated with the access key — and names the key contents (company/contact details, account settings, hourly API usage) plus the underlying endpoint. It is distinguishable from siblings like idx_get_account_type by describing the returned payload, though it never explicitly contrasts with that near-namesake.

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?

Usage is only implied: a no-parameter read that tells you about 'the access key' in use. There is no statement of when to call this versus idx_get_account_type or the various idx_list_* account sub-resources, and no prerequisites or exclusions.

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