Create or extend a local enum

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

With no annotations, the description carries the full burden, and it does disclose one genuine behavioral trait: the operation is idempotent. However it omits other relevant traits for a mutating tool, such as persistence (local to the database, requiring a save), permission needs, or what happens to existing members on conflict.

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?

A single front-loaded sentence with no waste. It is arguably slightly under-specified for a mutation tool, but it is not padded or redundant.

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 explained, and the parameters are well covered by the schema. Still, for a mutating tool with no annotations, the description should say more about scope and effect (local enum in the current database, non-destructive member upsert) than the single sentence provides.

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 'queries', the nested name/members/bitfield structure, and 'instance_id'. The description adds no syntax or format detail beyond the schema, which is the expected baseline when the schema does the heavy lifting.

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 pair (create/extend) and resource (local enums) and adds the distinguishing modifier 'idempotent way'. An agent can tell it apart from the broader type tools (declare_type, set_type), though it does not explicitly name which sibling is the non-idempotent alternative.

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?

There is no explicit when-to-use or when-not-to-use guidance, and no routing to alternatives like declare_type or type_apply_batch. The word 'idempotent' hints at a use case (safe repeated upserts) but leaves the choice between siblings entirely to inference.

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