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

Annotations declare readOnlyHint=false and openWorldHint=true, so the agent knows this mutates state, and the description adds the booking_via_agents=true precondition and the hand-off to extras/driver steps. It does not disclose the core behavioral trait of selecting an offer — whether it holds/reserves the offer, for how long, or whether it can be undone.

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, front-loaded with the action and its source, then prerequisites. No redundancy, though 'Bota then asks for extras or driver details as needed' is flow narration rather than definitional content.

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 state-mutating, session-dependent tool with no output schema, the description covers preconditions and downstream steps but omits what the selection produces and its lifecycle (hold duration, expiry, reversibility). An agent can call it, but not fully predict consequences.

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 75% and company_id, session_id, language already carry documentation. The description adds real meaning for offer_number by tying it to the numbered results of search_availability in the same session, but adds nothing for the remaining parameters. Baseline 3 fits.

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?

Specific verb and resource: 'Choose one of the numbered offers returned by search_availability'. It anchors the tool to its sibling search_availability and to the session flow, so an agent can tell it apart from confirm_booking and select_extras. It stops short of explicitly naming what it is not.

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 ordering context ('returned by search_availability, same session') and a hard prerequisite ('Requires booking_via_agents=true'), plus what follows next (extras or driver details). No explicit when-not-to-use guidance, but the sequencing is clear enough to route correctly.

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