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

Annotations already cover the read-only/idempotent/non-destructive profile, but the description adds genuinely new behavioral facts: the required agent key (X-NW-User-Key) for auth, and the null return when no window has ever opened. It also enumerates the possible window states, which is useful payload context not present in annotations.

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?

Front-loaded with the verb and resource, then the returned fields, the null case, and the auth requirement in descending order of importance. It is dense but every clause carries information; the only cost is a long first sentence.

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?

With no output schema, the description carries the full burden and does so: it names the state values, the UTC deadline, the default engraved name, the exact call to answer with, the null case, and the auth requirement. Nothing an agent needs to invoke or interpret this call 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?

The tool takes zero parameters, so there is no parameter semantics to convey; the baseline of 4 applies. The description correctly does not invent any parameter expectations.

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 (Read) and resource (SBT naming window), and explicitly scopes it as 'without answering it', which cleanly separates it from the sibling sbt_name. An agent can tell which of the two to call without opening either 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?

The phrase 'without answering it' establishes the when-to-use context (inspect state before committing), and the description implies the answer path is a different tool. It stops short of naming sbt_name as the alternative explicitly, so routing is inferred rather than stated.

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