Write File

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

Annotations already declare destructive=true and idempotent=true, and the description reinforces this with 'overwrite existing files without warning'. It adds context beyond the annotations: the sandboxing constraint ('only works within allowed directories') and the limitation to text content with proper encoding.

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?

Three short sentences, front-loaded with the core action and the destructiveness warning second. 'Handles text content with proper encoding' is slightly vague but still earns its place as a limitation statement.

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 two-parameter write tool with no output schema, the description covers the destructive behavior, the sandboxing constraint, and the text-only scope. It lacks error/failure behavior disclosure, but nothing critical to correct invocation is missing.

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 0%, so the description carries the burden for both parameters. It partially compensates by hinting that path is constrained to allowed directories and that content is text with encoding handling, but it gives no path format guidance (absolute vs relative) or content-size/encoding specifics.

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 specific verb and resource ('Create a new file or completely overwrite an existing file') and pins down the scope of what it writes. It does not name the obvious alternative (edit_file) for partial modifications, but the phrase 'completely overwrite' implicitly separates it from incremental editing tools.

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 warns 'Use with caution as it will overwrite existing files without warning' and constrains operation to allowed directories, which is useful contextual guidance. However it never says when to prefer this over edit_file or other siblings, leaving the agent to infer that from the word 'overwrite'.

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