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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety bar is covered. The description adds real value beyond that by disclosing the data source (council interest registers under the Local Authorities (Members' Interests) Act 1968) and the full content scope. Auth/pagination behavior is not mentioned, keeping it from a 5.

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?

Three sentences, front-loaded with the verb and resource, then content scope, then triggers. No filler or repetition; every sentence earns its place.

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 an output schema present, return values need not be described, and annotations cover the safety profile. The description supplies purpose, content scope, and legal provenance, leaving only minor gaps such as auth or rate behavior for a read-only tool whose parameters are fully documented.

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?

Schema description coverage is 100%, so the schema already documents council_slug, term, and include with examples. The description adds no parameter-level syntax or filtering semantics beyond the schema, which is the expected baseline at full coverage.

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?

Specific verb (Get) plus resource (pecuniary interests declared by councillors) plus scope (a specific NZ council). The list of included interest types and the statutory source make it unmistakable against siblings like get_interest_register or get_director_conflicts.

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?

Explicit triggers are given: conflicts of interest, council member business interests, local government transparency. No sibling is named as an alternative nor is an explicit 'when-not' provided, so it stops short of a 5.

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