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

With idempotentHint and destructiveHint already supplied, the description still adds real behavior: a new source_url is re-read within a minute and nightly, refresh: true forces an immediate read, and the call fails with plan_required on the free plan. It does not describe what happens to prior instructions when omitted, which keeps 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 tight sentences: purpose first, then the refresh timing, then the failure mode. Every clause carries information an agent needs, with no filler.

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, yet the description discloses the knowledge.refreshing state to expect and the plan_required error, and all five parameters are fully documented in the schema. Nothing essential for correct invocation 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 100%, so the baseline is 3, but the description earns credit by explaining the timing semantics of refresh relative to the automatic re-read within a minute and the nightly refresh. That adds meaning beyond the schema's terse 'Read source_url again now.'

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 states a specific verb and resource: turning a website's AI agent on or off and setting what knowledge it uses. This clearly separates it from read-only siblings like get_ai_agent and from create_site, so an agent can pick it without opening the 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?

Usage is implied rather than stated: the description covers configuration and refresh behavior, and notes the free-plan failure, but never explicitly says to use get_ai_agent for reads or update_site for site settings. The agent must infer the routing from the verb.

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