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

Annotations already establish read-only, idempotent, non-destructive behavior. The description adds the key behavioral fact annotations cannot: the tool requires a Floreal Workspace sign-in that this connection does not have, so calls will yield an error/guidance response rather than reservations. This disclosure of auth state and expected failure behavior adds real value beyond the structured data.

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 with the critical auth limitation front-loaded and the actionable instruction last. Every sentence carries information — requirement, function, and call-it-anyway rationale — with no filler or repetition.

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 zero-parameter tool with no output schema, the description covers purpose, prerequisites, failure behavior, and usage guidance — enough for an agent to invoke it correctly. It could optionally route users to siblings like 'arrivals,' but nothing essential for calling this tool 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 input schema has zero properties, so there are no parameter semantics to document; schema description coverage is 100% and there is nothing for the description to add. The baseline of 4 for a parameterless tool applies here.

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: 'returns the reservations departing on a day.' The conditional nature is handled honestly, with the sign-in requirement declared first and the fallback behavior (answering with what is wrong) explained. It doesn't explicitly name siblings, though the name/title pair naturally distinguishes it from the sibling 'arrivals.'

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 description gives explicit when-to-use instruction: 'Call it anyway when the user asks for this,' even though the connection lacks the required sign-in, because the tool's error guidance is 'what they need to hear.' This clearly resolves the counterintuitive case, but it stops short of naming alternative tools or explicit when-not conditions.

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