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

Beyond the readOnlyHint annotation, the description discloses the HTTP 200 behavior and the crucial semantic that estate:null means a measured absence rather than a missing/errored record. This prevents an agent from misinterpreting a valid empty result.

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 tightly written sentences, front-loaded with the core purpose and immediately followed by the one behavioral caveat that matters. 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 a simple read-only lookup, and the description covers the key ambiguity (null result meaning). It does not describe the non-null response shape, but no output schema exists and the intended answer is directly inferable from the purpose; a small note about unknown slugs would make it fully complete.

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 description adds no parameter-level meaning. Schema covers the optional context parameter, but the required slug parameter has no description, and the prose never states that slug identifies the provider. With only 50% schema coverage, the description does not compensate.

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 the exact relationship being queried ('which corporate estate a provider belongs to'), with the modifier 'if any' setting correct expectations. This is distinct from sibling tools like get_estate (fetch an estate directly) and find_estates (search estates), so an agent can select it based on purpose alone.

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?

Provides no when-to-use or when-not-to-use guidance and does not point to alternatives among the many sibling tools. The only contextual hint is the null semantics, which is behavioral rather than a selection criterion.

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