add_fields

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

With no annotations provided, the description carries full burden and does an excellent job disclosing behavioral traits. It explains what gets created (fields with specific constraints), provides detailed format requirements for default values, describes priority rules when conflicting defaults are specified, and includes important constraints about system field types and lookup field width requirements.

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 appropriately front-loaded with core functionality, but contains some redundancy (repeating system field type warnings) and includes an extensive example that could be streamlined. While most content is valuable, the section about alternative field naming approaches could be more concise.

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 tool with no annotations and no output schema, the description provides comprehensive coverage of what the tool does, how to use it, parameter details, constraints, and examples. The only minor gap is the lack of information about what the tool returns (success/failure indicators, field IDs, etc.), which would be helpful given the absence of an output schema.

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?

Despite 100% schema description coverage, the description adds significant value beyond the schema. It elaborates on the structure of the 'properties' object, specifies required sub-fields (code, type, label), provides detailed format requirements for default values, and includes a comprehensive example showing exactly how parameters should be structured.

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 clearly states the specific action ('adds fields') and resource ('kintone app'), distinguishing it from siblings like 'create_app' (creates entire app) or 'update_field' (modifies existing fields). It precisely defines what the tool does without being tautological.

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 description provides clear context about when to use this tool (adding fields to an app) and includes important exclusions (system field types cannot be added). However, it doesn't explicitly compare against alternatives like 'create_choice_field' or 'create_lookup_field' which appear to be more specialized sibling tools.

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