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

With readOnlyHint=false and openWorldHint=true already declared, the description still adds meaningful behavior: the URL is permanent, the return shape is {url, slug, version, token?}, and the token is issued only on the first anonymous publish and must be stored for later updates. That token lifecycle detail is real value beyond the annotations. It does not mention slug collision behavior or what happens to prior versions when publishing again.

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, each earning its place: trigger, action, and return contract. The stance call is front-loaded and nothing is padded.

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 6-param mutation tool with no output schema, the description compensates by spelling out the return object and the token lifecycle, and annotations cover the safety/open-world profile. Remaining gaps (merge vs. replace semantics, ttl interaction) are documented in the schema, so this is nearly complete.

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 every parameter (spa, slug, files, merge, token, ttl_seconds) is already documented in the schema, and the description adds no parameter-level detail. Baseline 3 is correct when the schema does the heavy lifting.

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+resource ('Publishes files to a live permanent URL at the chosen slug') and frames the user intent ('wants something put online, shared as a link, or hosted'). Clearly distinguishable from delete_site, get_site, list_sites, and update_site.

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?

Gives an explicit trigger condition tied to user intent, which is strong usage guidance. It does not, however, name the sibling update_site/delete_site as alternatives for editing or removing an already-published site, so routing between publish and update is left to inference.

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