create_custom_category

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

With no annotations provided, the description carries the full burden of behavioral disclosure. 'Create' implies a write operation, but the description doesn't state whether the category is globally available or profile-scoped, whether duplicate names are rejected, what happens to existing entries when a category is removed, or what the response contains. The profile_id parameter in the schema hints at scoping behavior, but the description itself discloses no behavioral traits.

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 description is a single short sentence with zero waste. It's front-loaded and immediately clear about the action. Nothing extraneous is included.

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 has nested objects (data object with its own sub-properties including schema_hint), 2 parameters, no output schema, and no annotations. The description says nothing about what a custom category is used for, how it relates to custom entries, what the schema_hint parameter controls, or what kind of response to expect. For a create operation with nested structures and no output schema, the description is notably thin—it should explain the category's role in the broader data model and clarify the purpose of schema_hint.

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 50% (2 of 4 total properties documented, though 2 are top-level and 2 nested). The description adds nothing about parameters beyond what the schema provides. The name and description fields are documented in the schema with 'カテゴリ名' and '説明' respectively. The profile_id field has a reasonably detailed schema description covering account vs profile-scoped key behavior. The description itself contributes zero parameter guidance, making it at baseline given partial schema 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?

The description 'カスタムカテゴリを新規作成' (Create new custom category) provides a clear verb+resource pairing, and given the sibling tools like update_custom_category and delete_custom_category, it effectively communicates that this is the creation operation. However, it doesn't specify WHAT a custom category is, what fields are involved, or how it differs from create_custom_entry, which is a closely related sibling. It's adequate but lacks contextual differentiation beyond the verb.

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?

No guidance is given about when to use this tool versus alternatives. There's no distinction between custom categories and custom entries, no mention of whether categories are required before creating entries, and no conditions or prerequisites described. The schema_parameter for profile_id partially explains account vs profile scoped keys, but this is in the schema, not the description. For a tool among many similar create_* siblings, this is insufficient guidance.

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