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

Annotations already declare destructiveHint=true and idempotentHint=true, and the description adds real value on top: full-file replacement semantics, the baseVersion optimistic-concurrency requirement, and the side effect that writing a new pages/<slug>.liquid also creates the page. It doesn't say what happens to concurrent edits beyond baseVersion or whether changes go live immediately.

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 short and front-loads the core behavior, then layers the prerequisite, the alternative, and path conventions. The JavaScript/asset_url sentence is useful but dense and slightly divorced from the main point.

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 destructive 4-parameter write tool with no output schema, the description covers the side effects, prerequisites, and path formats an agent needs. It could still mention size limits or whether a publish step is required, but nothing critical 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 coverage is only 50% (path and text are undocumented), and the description compensates by giving concrete path conventions (pages/<slug>.liquid, assets/<name>.js) and by spelling out the baseVersion rule. The meaning of 'text' as whole-file content is only implied.

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 uses a specific verb ('Create or replace') and resource ('a whole file of an HTML-first site'), and explicitly contrasts itself with read_site_file and edit_site_file, so an agent can distinguish it from its siblings.

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 states the prerequisite for replacement (baseVersion from read_site_file) and directs the agent to edit_site_file for smaller changes, giving both when-to-use and when-to-use-an-alternative.

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