fs_write

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

With no annotations, the description carries the full burden of disclosing behavioral traits. It explicitly states that directories are created if needed and that escaping is handled correctly, which are important side effects beyond a basic write. However, it does not mention overwriting behavior, permission requirements, or error handling.

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 sentences with no extraneous words. Each sentence adds valuable information: the core function, automatic directory creation, and correct escaping. No fluff or redundancy.

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 simple tool with only two parameters and no output schema, the description is fully adequate. It covers the core functionality, key side effects, and a behavioral guarantee (escaping). No gaps remain at this level of complexity.

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 coverage is 100%, so the description's job is to add value beyond the schema. It does add context about directory creation (relevant to path) and escaping (relevant to content), but these are minor enhancements. The 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 clearly states the verb 'write' and the resource 'file', and mentions additional behaviors (creates directories, handles escaping) that distinguish it from sibling tools like fs_read, fs_search, and fs_list, which are read operations.

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 no explicit guidance on when to use this tool versus alternatives (e.g., fs_read for reading, or shell commands for file manipulation). There is no mention of prerequisites, exclusions, or preferred use cases.

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