create_custom_entry

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

No annotations are provided, so the description carries the full burden. It only states the action without disclosing any behavioral traits—whether profile-scoped vs account-scoped API keys behave differently, what validations exist on the free-form JSON content, whether edits are reversible, or whether category_id must exist beforehand. With zero annotation coverage, this is a significant gap.

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 concise sentence in Japanese with no waste. However, it's underspecified—it's so brief that it provides minimal value. Conciseness done well would combine brevity with meaningful content, but here brevity sacrifices informational 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?

The tool has nested objects, 2 parameters, and no output schema. The schema covers parameters fairly well despite 50% coverage. The main missing context is how this tool relates to custom_categories, whether there are validation rules on content, and what the return value is. Given moderate complexity (nested objects, free-form content), the description is somewhat thin but the schema partially compensates.

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%. The description adds no parameter-level information. However, the schema itself documents parameters fairly well (title, content as free-form JSON, confidence, importance, tags, metadata, category_id, profile_id with binding rules). The profile_id description in the schema provides useful context about scoped API keys. The description itself adds nothing beyond what the schema already provides, so baseline 3 is appropriate.

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 'カスタムエントリを新規作成' (Create new custom entry) has a specific verb (create) and resource (custom entry). It's clear and distinct from siblings like update_custom_entry, delete_custom_entry, and get_custom_entry. However, it doesn't explain what a 'custom entry' is or how it relates to custom_categories, which could improve clarity.

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 on when to use this tool vs alternatives. It doesn't discuss the relationship with custom_categories (the category_id parameter suggests custom entries belong to categories), or when one might prefer create_career_entry/create_skill/create_achievement over this generic tool. No when/when-not guidance given.

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