create_new_file

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 discloses the key behavioral trait: requires planKey from whoami, and it explicitly warns against calling when a file is open. It also states the expected output. It does not elaborate on side effects, error handling, or reversibility, but for a file-creation tool the key constraints are covered, making it largely transparent.

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 compact and well-structured. It front-loads the purpose, states the expected output clearly, and places the critical usage constraint (planKey and alternative tool) in the IMPORTANT note. Every sentence earns its place with no fluff.

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 four parameters, three required, and no output schema, the description is complete: it explains the purpose, prerequisites, expected output, and usage boundaries. The combination of schema coverage and description covers everything an agent needs to call it correctly.

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 all parameters, including the planKey pattern, potential values for editorType, and optional projectId. The description adds no new parameter meaning beyond what the schema provides; the only extra mention is that planKey comes from whoami, which is already in the schema description. Baseline of 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 states a precise verb (creates), a specific resource (new Figma design, FigJam, or Slides file), and the scope (drafts or specified project). It also explicitly distinguishes from the sibling use_figma by specifying when not to use it, so an agent can clearly separate it from alternatives.

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?

It gives explicit when-to-use context (create a new blank file) and when-not-to-use (if user already has a file open, use use_figma instead). It also names a required prerequisite (planKey from whoami), making the usage conditions unambiguous.

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