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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds real value beyond that by enumerating the payload contents (status, channel, dates, guest information, notes, assignee) and mapping to the concrete Hostfully endpoint GET /api/v3.3/leads/{leadUid}, which helps an agent anticipate the response shape given there is no output schema.

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?

A single dense sentence that front-loads the verb and scope, plus a short endpoint reference. No filler; each clause (lead subtypes, returned fields, API path) carries distinct information.

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 simple single-record read with readOnlyHint and no output schema, the description supplies the returned-field inventory and API mapping, which is enough for correct invocation. It omits only edge behavior such as what happens when the UID matches no lead.

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?

Only one parameter (lead_uid) and schema description coverage is 100%, so the schema already carries the semantics and the baseline is 3. The description restates 'by UID' without adding format, source, or retrieval guidance beyond the schema.

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 (Fetch) and resource (one lead) with scope qualifier 'by UID', then disambiguates the domain term by enumerating what a lead can be (booking, inquiry, booking request, block). An agent can distinguish this from create_lead, update_lead, and search_leads from the description alone.

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 'by UID' phrasing implies retrieval of a single known record versus a search, but the description never explicitly names hostfully_search_leads as the alternative or states when to prefer one over the other. Usage is inferable but not spelled out.

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