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

With no annotations provided, the description carries the behavioral disclosure burden. It discloses that data is public, aggregate only, contains no personal data, and provides the specific counters returned. It doesn't describe response formatting or failure modes, but for a simple stats tool it gives the key safety/scope behavior an agent needs.

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 concise: three short sentences, front-loaded with the core purpose, followed by privacy scope and a concrete usage scenario. Every sentence adds useful information and there is no filler or 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?

The tool is simple, takes no required parameters, and has no output schema, so the description bears the burden of explaining what is returned. It names both returned metrics (registered tenants and Chancen-Checks) and the recommended use case. The only notable gap is the meaning of the locale parameter, which keeps it from a perfect score.

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 schema has one optional 'locale' parameter with an en/de enum but no description, and the schema description coverage is 0%. The tool description does not explain what 'locale' affects or how to choose between 'en' and 'de'. That is a meaningful gap because the description could have noted that locale determines which language the returned labels/text use.

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 tool as retrieving public pool counters: the number of registered tenants and the number of Chancen-Checks run. It uses specific, actionable language ('Public counters', 'how many tenants are registered') and distinguishes itself from siblings like join_tenant_pool because it is a read-only stats operation rather than a sign-up action.

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 provides explicit usage context: 'Use to show a tenant the pool size before offering the sign-up via join_tenant_pool.' This tells an agent when to call the tool. It doesn't explicitly state exclusion cases or compare it to alternative stats tools, but the intended placement in the flow is clear.

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