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

Annotations already declare readOnlyHint=true and the description is consistent with that. Beyond annotations it adds the returned status values (building/built/failed), the no-auth guest mode, the polling interval, and the consequence of a duplicate create_site call — rich behavioral context an agent could not infer otherwise.

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 tight sentences, front-loaded with the purpose, then the two auth paths, then the polling anti-pattern. No filler; each clause carries actionable 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?

No output schema exists, but the description enumerates the status return values, covers both auth modes, and gives polling guidance — so an agent has everything needed to call it correctly and interpret the result.

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 both parameters are already documented, but the description adds the crucial semantic that slug applies to signed-in flows and claim_token to guest flows and requires no auth. This mode-selection meaning goes beyond the field descriptions, though the required/optional dynamic (both optional) is only implicit.

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 (check) and resource (site build status), and ties it to create_site so it is unmistakably the follow-up tool. An agent can distinguish it from siblings like get_site or create_site from the description alone.

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 spells out both invocation paths: signed-in callers pass the slug from create_site, guest builds pass claim_token and work without signing in. It also states the polling cadence (every 30-60 seconds) and warns against re-calling create_site, which would build a second site.

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