write_file

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

With no annotations, the description carries the behavioral burden. It discloses validation, refusal to write, automatic stamping of `updated` and `date`, and conditional writes via expected_etag. It does not mention overwrite semantics or failure details on ETag mismatch, but core behavior is 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?

Three concise, high-information sentences. The main behavior and key conditional flow are front-loaded, and there is no filler or redundant restating of schema fields.

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 3-parameter tool with an output schema and no annotations, the description covers the important conceptual pieces: validation, automatic mutation, and conditional writes. It could be more complete about overwriting behavior or what happens when the ETag does not match, but it is largely sufficient.

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 must compensate. It usefully explains expected_etag's purpose and the frontmatter-validating nature of content, but path is left entirely to its name and no content structure details are given. This partial compensation earns a mid score.

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 identifies a write operation on a vault file, with specific behaviors: frontmatter validation, refusal on invalid schema, and automatic field stamping. This differentiates it from sibling tools like append_file, move_file, and delete_file.

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 implies usage context through 'Pass expected_etag from read_file to make the write conditional,' which also hints at sequencing with read_file. However, it does not explicitly contrast this tool with alternatives like append_file or state when not to use it.

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