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

Annotations only carry destructiveHint=true, so the description does real work: it discloses merge/partial-update semantics, the Hostfully permission caveat that personal-data fields may be silently ignored, and the underlying PATCH endpoint. It stops short of stating whether omitted fields are preserved on nested guest objects or what the response contains.

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 with zero filler; scope, exclusions, and the permission caveat are front-loaded before the endpoint reference. Every sentence earns its place.

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 destructive PATCH with no output schema and partly documented nested params, it covers what is mutated, what is excluded, and an auth-related silent-failure caveat. Missing only merge-merge/null-clearing behavior and any hint at the return payload.

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% on a nested guest object, and the schema itself already documents date formats and 'omitted fields are kept'. The description adds category-level meaning (name, contact, address, arrival/departure) but no syntax beyond the schema, so baseline 3 is appropriate.

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+scope ('Partially update a lead's notes, extra notes and guest details') and immediately bounds it with what it does NOT change (dates, party size, property, status). This lets an agent distinguish it from hostfully_create_lead, hostfully_get_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 'partially update' framing plus the negative scope list makes clear when this tool applies versus full lead creation. However, no sibling is named as the alternative when the excluded fields (dates, party size, status) do need to change, leaving that routing to inference.

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