pp_get_categories

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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered structurally. The description adds non-obvious behavioral context beyond that: the call is cheap and its typical outcome is a mapping from natural-language terms to slug values, which tells the agent it is a cheap prerequisite lookup rather than a result-producing query.

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 sentences, front-loaded with what the tool returns and then the usage instruction, with no repetition of the title or schema. The closing clause ('Cheap, and worth it before a search that would otherwise return nothing') is slightly persuasive rather than informational but still carries real decision value.

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?

No output schema exists, so the description usefully enumerates the fields returned (Dutch display names, product counts, group) and the slug-oriented purpose, which is enough to call it correctly. It stops short of describing the response container or how to map a returned row to a `category` slug value.

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 and the schema is a closed empty object, so there is nothing parameter-wise to document; the baseline for no-params tools applies. The description correctly implies no input is needed, though it never literally says callers pass nothing.

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 resource returned (unified categories with Dutch display names, product counts and group) and pairs it with a named sibling relationship ('Call this before `pp_search`'), so the agent can distinguish it from the many pp_get_* deal/list tools without opening a schema.

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 when-to-use: call this before pp_search to translate a user's informal word ('zuivel', 'brood') into a valid `category` slug. It also gives the failure condition it prevents (a search that would otherwise return nothing), which is exactly the routing guidance an agent needs.

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