interests_categories

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

No annotations are provided, so the description carries the full behavioral burden. It conveys that this is a reference/lookup operation over declaration categories and discloses nothing dangerous, which is proportionate for a zero-parameter list. It adds nothing about scope, completeness of the category list, or how it differs from get_interest_category.

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 purpose is front-loaded in the first sentence, but the trailing 'Returns: Categories of interests that must be declared.' simply restates the opening sentence and is redundant, especially since an output schema already exists.

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?

For a zero-parameter enumeration tool with an output schema, the description covers what is needed to invoke it correctly; return structure can be read from the schema. The only gap is disambiguation from sibling interest-category tools.

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 the schema has nothing to document and the baseline of 4 applies. There are no argument formats or defaults an agent needs from the description.

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 ('Get categories of interests that MPs and Lords must declare in the Register of Interests'), making the subject matter unambiguous. However, it does not differentiate itself from close siblings such as get_interest_category, get_registers_of_interests, or get_policy_interests, which an agent must choose between.

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 sentence 'Use when you need to understand what types of financial or other interests parliamentarians must declare' gives implied usage context, but names no alternatives and no when-not-to-use conditions. With several similarly named interest tools in the sibling list, routing guidance is the main missing piece.

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