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

Annotations already declare readOnly/non-destructive/non-open, and the description adds real value on top: the login is masked and the password is never returned (security posture), plus the two billing models (workspace account vs. managed budget with account.source = "managed"). It does not describe pagination or refresh semantics, so it is not exhaustive.

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?

Front-loaded with the purpose, and every clause maps to a distinct returned field with no filler. It is one very long comma-chained sentence, which is dense but not wasteful.

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, so the description properly carries the return-value burden by enumerating the configuration fields (account mode, domains, schedule, engines/devices, spend). Nothing an agent needs to decide or call the tool 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?

Single clientId parameter at 100% schema coverage, and the schema already documents it as coming from list_clients. The description adds no syntax or format detail beyond the schema, so the baseline 3 applies.

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 precisely what is retrieved – the rank-tracking configuration for a client (engine/budget mode, domains, schedule, engines/devices, cost). This clearly distinguishes it from get_rankings (positions) and set_rank_schedule (mutation), though it never names a sibling explicitly.

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?

Ends with an explicit prerequisite: "Read this before adding keywords or starting a refresh." That tells the agent when to reach for it in a workflow, but it names no alternative read tool and gives no when-not condition.

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