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

Annotations only supply the generic safety profile (destructive/openWorld/non-idempotent); the description adds concrete failure semantics (booking_destination_unmapped, honest failure instead of fabricated confirmation), the no-charge guarantee, platform limitations, and async behavior. This is exactly the beyond-annotation context an agent needs.

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 core verb set, then dense but each clause carries distinct information (precondition, failure mode, platform limit, price, async tag). Slightly overloaded with bracket tags, but no wasted 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 correctly focuses on behavior and failure modes and is fairly complete for a complex, destructive, async tool. Its one real gap is the undocumented parameter surface, which the description leaves entirely to a low-coverage schema.

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 only 25% across 8 params with nested objects, yet the description explains no individual parameter. It implies the action set and no-charge behavior but never clarifies smb_id, service, customer, requested_time, or how the idempotency_key interacts with the 24h replay.

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 set (check availability, book, cancel) against a specific resource (Cal.com appointment) and the enum matches exactly. It is immediately distinguishable from siblings like check_booking_link or import_booking_url.

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 a clear precondition (the SMB's imported booking link must be bound to the one connected Cal.com account) and routes async callers to get_outcome via '[async→get_outcome]'. It does not, however, say when to prefer check_booking_link or import_booking_url over this tool.

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