Write local file

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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description adds genuinely useful context beyond that: the overwrite is 'complete' (existing content is destroyed, not merged) and parent directories are auto-created, which affects how the call succeeds or fails. It does not mention permission/error behavior, keeping it from a 5.

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, all front-loaded: what it does, then the directory-creation side effect, then the routing hint. No filler and every sentence carries distinct information.

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?

An output schema exists, so return values need no explanation, and the annotations carry the safety profile. For a two-parameter mutation tool, the description covers purpose, side effects, and sibling routing adequately.

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 both parameters (path, content) are already documented, making 3 the baseline. The description adds the UTF-8 encoding and 'complete contents' framing for content, but nothing extra for path.

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?

States a specific verb and resource ('Create or completely overwrite a local UTF-8 text file') and immediately distinguishes itself from the sibling 'edit' by contrast. An agent can tell it apart from read/edit/bash without opening any schema.

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?

Explicitly names the alternative ('Use edit for a targeted change to an existing file') and gives the condition that selects it. The overwrite semantics also implicitly state when not to use this tool for incremental edits.

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