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

Annotations only supply destructiveHint=true, so the description carries real additional load: it discloses PATCH-style partial-update semantics, that omitted guest fields are preserved, that personal-data fields may be silently dropped by key permissions, and the underlying endpoint. It does not state reversibility or what the response returns, but the mutation behavior is well disclosed.

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 tight sentences, front-loaded with the write scope followed immediately by exclusions and the permission caveat. Every clause (including the endpoint) carries information; nothing is padded.

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?

No output schema exists, so the description is the only place return behavior could be described, and it is silent on the response shape. Otherwise it is complete for a partial-update tool: write scope, exclusions, preservation of omitted fields, and permission risk are all covered.

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 50% with four top-level params, and the description enumerates the guest sub-object contents (name, contact, address, arrival/departure times) plus notes and extra notes, mapping each top-level parameter to its purpose. It adds grouping context the schema only partially provides via the nested "Guest fields to change" note.

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 (partially update), resource (a lead), and scope (notes, extra notes, guest details), then explicitly rules out dates, party size, property and status. An agent can distinguish this from hostfully_get_lead, hostfully_create_lead and hostfully_search_leads 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?

The "Does NOT change dates, party size, property or status" clause is explicit when-not guidance, and the permission caveat tells the agent fields may be silently ignored. It stops short of naming which sibling to use for those excluded fields (e.g. a status/date change tool), so it is clear context rather than full routing.

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