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

Annotations already cover safety (readOnly, idempotent, non-destructive), yet the description adds real behavioral context: nothing is reserved or held, an open date can still sell out before checkout, unsupported product categories return 'unsupported' with a page link, and there is a 31-day-per-call cap. These are non-obvious operational traits not derivable from 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 user-intent trigger and example phrasings, then prerequisites, exclusions, and limits. Dense but every clause carries information; it could be split for readability but there is little waste.

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?

Given an output schema exists, the description needn't detail return structure, yet it usefully summarizes the tri-state result (open/closed/unknown) and the unsupported case. Combined with prerequisites, limits, and exclusions, an agent has everything needed to call it correctly in one shot.

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 description coverage is 100%, so the baseline is 3; the description adds value beyond the schema by explaining the provenance of product_id (must come from search_travel_products) and which product_id prefixes are supported versus returning 'unsupported'. It does not restate the locale enum or date format, which the schema already handles.

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+resource (check whether a given OlaChill tour/ticket is bookable on certain dates) and names the exact upstream tool that supplies the required product_id (search_travel_products). An agent can distinguish it from siblings like search_travel_products or get_booking_status without opening any 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?

Gives explicit when-to-use triggers with example user phrasings, an explicit prerequisite ('call search_travel_products first if you do not'), and explicit exclusions (not for booking, charter coaches, transfers, helicopter flights, or without a product_id). Nothing is left to inference.

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